Your luckier than me. I'm trying to find current info to swap v6 to v8 in my 2002 s10, but not too many people have done it with the 2002'*.
Anyhoo. I'll answer your last question while my video uploads...
Boost valve solenoid requires 2 wires. 1 GND and one from the PCM. Which pin, I do not know with your year/make. Basically, you have to ADD one wire to your PCM for the boost solenoid. And yes, your stock N/A harness will work fine. Mine did.
I see an issue. In your 2nd picture, your ICM bracket is painted red. On your harness, you will find an eyelet wire that needs to be mounted on one of the bolts for that bracket. I couldn't get a shot of it in the video. But either way, you need to scrap away the paint for a good connection. It'* a ground for the ICM.
Normally, your MAP sensor mounts in a different location on the N/A vs the */C. If you plan on placing it in the L67 STOCK location, you will need to extend the harness for the MAP sensor by 8 inches or so. Or, you can place it wherever you like, because its only 1 single vac line that connects to it.
I just took this video of the pulley'* for ya. Hope it helps.
L67 belt/pully - YouTube