I just finished my engine installation on my 90 740T, but due to some issues, It's going to be parked until further notice - I'll probably deal with it mid June, when my semester is finished.

Next time it will be a much more systematic approach, involving more testing than throwing parts at it.

Today, I drove the car about 40 miles without bothering to check the splices for the dash temp gauge. While going over a mountain pass, I lose the lower radiator hose and all my coolant. Pulled over before I knew what had happened because I thought I glimpsed smoke out the tailpipe and found the problem.
The car threw a check engine light with 2 codes: 2-4-1 EGR and 2-2-4? ECT out of range or failed. Sounds like it got warm. I've never thrown an engine code with an overheating situation before. I hope nothing warped or blew, or it will be pick-n-pull or part-it-out time.

I did not know it, but the lower radiator hose had deformed and softened. Before doing anything else with the car, I will install all new hoses, in addition to the new thermostat and heater hoses I had installed. I think the oil in the coolant from the old engine's blown HG may have damaged all of the hoses.

Anyway, I'll be taking care of maintenance and some minor suspension work on my 84 244DL in the mean time.
A new car seems fitting for my new adventures ;)

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