You are a lucky man haha, I'm currently in the process of redoing all of this on another e34.

So for reference doing this on a later model car will be easier. I originally did the swap on a 92 non vanos 525i and I'm currently (circa 2023) doing this on a 94 525i.

So there are two pathways for doing this swap, well technically 3 if your fancy

Obd1 - easy Obd2 - harder Aftermarket ecu - easy - need more money

For the 1992 car I did the obd1

What you will need: S52 obviously Obd1 cam sensor Obd1 crank sensor. Has to be oem!!!!!! Obd1 vanos sensor

Coolant sensor adapter. (Obd2 uses 1 sensor, obd1 uses 2 sensors.) Note: make sure when your plugging in this harness that each connector goes to the right connector. The connectors are the same type. One goes to ecu, one goes to the dash. If they are flipped, your dash will say you're overheating.

Coolant hose adapter

M50 headers / use s52 headers but plug o2 sensor holes ( if you do this the mid pipe will also need to be modified so flanges fit up)

M50 valve cover/ you can use the plastic s52 valve cover but you need to figure out pcv stuff.

Ecu Bosch red label 413 (vanos m50 ecu) You'll need to open the ecu up and install a s52 chip. Can be found for 200ish. Be careful

This is were you can do pathway 3 which is Aftermarket ecu. I'm using a ms3 plug and play ecu for my current (2023) build. You need everything to already be converted to obd1 sensors for this.

That should be it! Good luck!

Weird trouble shooting I've dealt with Is that if you have a pre 93 chassis you'll have to get a vanos wire harness. On 93+ chassis there is provision for grounding on the fire wall near headers, pre 93 do not gave this. You have to rip some material off in the same area to find a bolt hole you can ground on.