I'm not familiar with hybrids at all so if/when I go to check this truck out what/where should I look for?
Here's a few things I would check for
1.
Is the speedometer hooked up and if so does it work? The speedos on S-10's since 1988 were electronically operated. Many times on S-10's when a V8 or other non stock engine has been swapped in, the speedo is not hooked back up.
2.
Do the reverse lamps work? Again I've seen this on converted S-10's...the reverse lamps are not hooked up. That's what we mean by "thrown together"...some just drop in the engine/trans, hook up the exhaust, make sure there's a fuel and ignition source and that's it...to hell with all the sensors, gadgets and reverse lamp switches. <--shade tree mechanic logic
2.a Also make sure all the exterior lights and the wipers and hazzards work too.
3.
Does the engine overheat? Especially on converted V8 S-10's sometimes the radiator isn't up graded and so you end up with an overheating engine. Also make sure they used electric fans and if possible make sure they're in the "puller" mode, or inside the engine compartment, as this works better than the pusher mode. (outside engine compartment)
4.
Does the truck still have the stock 7.625 rear end? 98% of all S-10's used a 7.5 or a 7.625 rear, both are weak. Only the ZR2 S-10's and the '96 and up S-10's with the high output 4.3/5 speed combo go the 8.5 rear. The rear pumpkin on an S-10 looks just like the one on a TR/basic Regal RWD.
5.
Does the a/c in the truck work? I see he says it has a/c but the big ? is did he hook the a/c up and does it blow cold?
6.
Does the heater work? I only ask this because I saw once where a guy ripped off the heater box under the hood to make room for a 327 in his S-10...the whole squirrel cage and all was exposed....again a hack job...and he didn't have any heat.
7.
Does the truck have posi traction? Trust me you will want/need it.
8.
What kind of motor mounts were used to put the engine in? This is another one...I saw an S-10 once where they used the wrong motor mounts and instead tack welded the improper ones right to the frame! Now if that's not shade tree jimmy rigging at it's best....improper motor mounts are going to cause you some issues.
9.
Was the floor board clearanced for the down pipe? An S-10 engine bay is a tight fit, and the few LC2'd swaps I've seen required the pass side floor board to be cleared for the downpipe....passengers feet might get warm, or you might hit the dp setting off the knock alarm.
These are a few I can think off the top of my head.