Here's a photo of the current antenna setup on the truck. The left antenna is the HF-6m screwdriver (ATAS-120A). The center antenna is the M2 HO Loop. And the right antenna is the vertical 5/8w dual-band.
After the January VHF Sweepstakes, I decided to order the M2 2m HO Loop antenna so that I could operate VHF-SSB Mobile. I already had the dual-band 2m/70cm vertical antenna mounted on the right of the truck box, but for SSB work I needed a horizontally-polarized signal and the reviews of the HO Loop were pretty good.
The loop installation and tuning were pretty straightforward. The loop is attached to a 22" 3/8"x24 stainless steel mast, which connects to an L-bracket in the center of the truck box using a quick-release coupling. I had to shave off 1/8" from each of the aluminum ends of the HO Loop in order to bring the antenna to resonance at 144.500, and there it has an SWR of less than 1.1:1; at 144.200 the SWR is less than 1.2:1. Reportedly, water will detune the antenna slightly downward, so that's why I tuned slightly high.
While mobile, I've been able to routinely make contacts up to 90 miles away, and during nets I can hear 20-30 stations in the local area. So far so good!