[Flieger]

Disclaimer: I am not an expert, nor do I have shop experience. I am just an enthusiastic student of the big guns.

The 3.2 crankshaft is 74.4mm stroke. 2.8 RSR was 70.4mm stroke.

3.2 case is Aluminum (good for strength, of course) but the head stud-spacing is wider than the 2.8 RSR, I believe.

Your 3.2 rods are weaker (narrower) than earlier rods.

I would look for a 2.7 with reinforced 7R case or 3.0 liter to be more correct.

If you get an early motor like a 2.0 with MFI you can use JE pistons and LN Engineering cylinders in 90mm bore for a 66mm stroke x 90mm stroke high RPM screamer. 2.5 short-stroke MFI - like in the 911ST. You can make more than enough power out of that. Much more than a 2.7 RS spec (210 hp, 188 lb-ft.)

If you find a 2.2 or 2.4 motor that is tired, you can use the MFI and case and build a 2.7 RS spec+ with RSR power. Use higher compression (10.5 vs 8.5 :1) and twin plug (if the Supertech distributor is in your budget)

MFI can be expensive to recondition the injection pump but the performance is thrilling. Any pump can be tuned to work on your displacement.

I think you should sell the motor you have now unless you want to buy a crank and more.