I'm getting ready to make a run at this. The hardest part was finding a configuration of the powersteps that has either
a) brackets meant to mount on f a horizontal/flat surface (torsion boxes for the K5)
b) brackets meant to mount on the frame and extend outward.
Most of their configurations are meant to mount on a vertical inner surface of the rocker panel, which obviously isn't an option for the K5's because of the torsion boxes.
So, I used
this diagram of replacement motor linkages and just generally going through the Amp Research website and looking at EVERY installation guide to see what would work best.
Scenario 'a' yields either the Wrangler, Colorado, Tundra, Cherokee, or Durango variants while scenario 'b' yields either the Forerunner, Tacoma, or H2 variants.
I'm literally carrying a tape measure around with me and trying to measure some of these cars with the critical dimensions being inside of pinch-weld to outside of rocker panel for scenario 'a' and outside of frame to outside of rocker panel for scenario 'b'.
So far, my leading contender is to mount them to the torsion boxes using either the Chevy Colorado variant or one of the wrangler variants. The Colorado has the slimmer board profile, but seems to be OBDII-triggered only. The Wrangler setup seems to be available with 12V inputs, but has a chunkier board profile. The only other tempting option is the Tundra since it doesn't require any pinch-weld bracketry. However, it's not clear whether the Tundra mounts are in plane with the road surface like the bottom of the K5 torsion boxes.
I'm going to contact AMP about the OBDII triggering and then make a call.