I just finished the engine swap for my 90 740 turbo! Charged the old battery after adding a little distilled water to it, installed everything, including coolant and oil, and it started right up after I tightened down the fuel feed line.

Thanks to everyone that helped me, I removed the blown 87 b230ft with unknown miles (I put 100K on it) and installed a 93 b230ft from a crashed 944T successfully.

I'm going to compile a write-up for it because I don't know of one and most of the time I wasted was on minor stuff, not on major components of the swap. Important detail I overlooked was using the turbo oil feed line that was on the replacement car - it's incompatible even though it looks like it fits.

Happy bricking and Happy New Year!
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1990 740 Turbo, on its way to stock specs, maybe beyond