Need help with manual conversion on E34 535

[535er 0]

Hey all Bima fans

Just managed to pick up a manual conversion for my E34 535, yes you heard right, MANUAL! WITH EVERYTHING!

Need some guidelines to follow, especially with that little plug that plugs into the trans etc. I was told I will have a trans warning come up on the computer & need to either earth the black wire out that goes to the trans or something, not quite sure

If anyone can give me any pointers, it would be greatly appreciated