Below are a few quick photos of my HF antenna installation. Click on the small thumbnail photo for a larger image.
 

There is not much really unique about the installation, other than perhaps that I use a wide solid copper strap to provide a more weather resistant, low inductance ground the base of the antenna. It is well known that the quality of the ground at the base of our short HF verticals has a direct influence performance of the antenna, probably more than any other single factor. I've seen too many installations where the use of braid (tinned or otherwise) starts to corrode from the effects of weather in a very short time, even here in New York, where we don't have a particularly humid or salt air environment. A braided ground installation that works well at the outset will slowly deteriorate over time as the individual strands of the braid corrode. Of course, if your particular installation requires that the ground strap be able to routinely flex, say for the opening and closing of a trunk or rear hatch, you'll have to  use flexible braid in any case. In my case I cut the 1 1/2" wide ground strap from a roll of copper roof flashing. You may not find this at your typical home improvement store, but copper flashing is still used by some professional builders in their upper end homes, at least around my neck of the woods. Naturally the ground path from the antenna base to a good vehicle ground needs to be as short as possible.  This will be dictated by the choice of mounting location and the constuction of the vehicle. In my case I would intuitively have preferred to have a shorter path to chassis ground. But with all the intermediate connections between the rear bumper framework near the antenna mount and the chassis itself, I wasn't convinced that this would provide the best ground. Thus the path of my strap to the body behind the tail light housing. Not shown in the photos is the waterproofing of all connections. Proper waterproofing is extremely important if you want exterior connections to maintain their complete integrity over time. Just at the top of the right angle coax connector I applied a little moldable coax-seal right to prevent water from flowing down into the connector. I followed this with one layer of 3-M rubber splicing tape around the coax connectors starting from the base of the antenna mount to where the cables enter the flexible wire loom conduit (Radio Shack). For additional physical protection, that's then covered in a layer of vinyl electrical tape, wrapped in the opposite direction. Everything was then coated with a clear acrylic spray for even more moisture resistance.  At the Ground strap connection at the base of the antenna I applied Penetrox abrasive corrosion inhibiting semi-conductive grease between the mount, the copper strap, the washer and nut. (You can also use NoAlOx, Ox-Guard or similar.) This was covered in moldable coax seal and oversprayed clear acrylic spray to flow into any remaining crevices. The ground strap connection behind the taillight is in an area that is not directly exposed to water. Nevertheless, I applied conductive grease between the body panel (ground down to bare metal), the copper strap, washer and bolt, and oversprayed this too with acrylic spray.  The connections on the small red matching coil between the antenna feed point and ground were done the same way. (A buddy of mine, N2KI, enclosed the matching coil on his installation within a plastic 35mm film cannister to help protect the coil body itself from the elements. The coil is well varnished as it comes from Tarheel, and I've so far seen no degradation of its finish even without that extra protection). The antenna's motor drive and position sensor leads run to the antenna through a four conductor water resistant trailer lighting connector. I took no specific steps to waterproof this further other than to use some NON-conductive grease on the contacts of that connector's plug and socket. Experience with my three trailers proves that this last step is well worth doing to preserve electrical contact and ease of insertion/withdrawal over time. And if you've thought ahead, yes, the antenna is quickly removeable. Tarheel supplies a nice hefty stainless steel Quick Disconnect connector at the base of the antenna. I added another brass QD between the top of the loading coil and the stainless upper whip. I can remove and stow the antenna in the vehicle in about 20 seconds. All Tarheel mounts and hardware are of stainless steel, so I have no qualms about leaving the mount exposed.  Oh yes, the body, hood, and exhaust system are bonded to the chassis at several points, too. The factory already had straps at several places (probably as EMI protection, inbound and outbound, for their multiple computer control modules in this vehicle. I added a couple of others where I thought they would help. Power to the rig is through 8 gauge wires run directly to the Positive and Negative terminals on the battery, using longer extension bolts (available from GM and others) to provide appropriate heavy connection points on the Yukon's side-terminal battery. No matter how well your antenna is able to pull out weak signals, if the RF background noise in your mobile receiver is high you just won't pull them out. Luckily, the RF noise level in the Yukon is not too bad, although I'm certainly glad I have the FT-100D and its absolutely superb noise blanker. With my installation I have a noise level of about S-2 on 20m while on the road. The setup performs exceptionally well. Although I have no comparative measurements of transmitted signal strength, I routinely get unsolicited comments from other stations about the strong, clear signal. I've even had other ops on 20 and even 40 meters often question whether I'm really mobile. I'm very happy with my Tarheel antenna installation, as it's working even better than I anticipated.