Which engines do and don't go into a mk2? I know there is quite a bit of interchangability between VAG stuff, so you could probably shoehorn in a lot of stuff, but I mean within reason, ie. fairly well known/documented swap.
So far i can think of:
9a 2.0
ABF 2.0
VR6 2.8 and 2.9
various flavours of 1.8t
any others?