I don't use a belt tensioning tool. My fingers are calibrated!!
Really I don't use one.
84's don't have cross over chains. Just the four valve per cylinder models.
The MS does have an input for a knock sensor but does not use this to retard the timing when the engine is pre detonating. This is critical for keeping the pistons together and/or not blowing the bottom end out of the car. The 951 (turbo) uses one.
The inter cooler on the 951 goes in front of the radiator. The inter cooler on the 924's went beside the head on the passenger side. Used a hood scoop to feed it fresh air. This was an upright/vertical inline four.
You will need a TDC sensor as well as an engine speed sensor. Since the 944 is already set up for the stock sensors (hint: the BMW sensors are the same but cheaper) best to use them.
Also need the throttle body off of a turbo with the throttle valve position sensor. Unless the turbo TPS can be fitted to the N/A throttle body.
No MAS? Interesting. Guess they use the throttle valve position feed back. Not the best thing to do but I guess it would work.
Once you get it together I figure about two weeks of driving before you break it big time. The N/A engine is not designed to handle that kind of HP.
I don't know everything. Sometimes I just make things up. YMMV.