1.8t 20v conversion or similar

hello you lovely bunch of people
after getting my mix match engine that's been sat up for a.number of years to actually turn over I think it's in need of being stripped cleaned and played with but with time effort and money I'm thinking a complete engine swap is in order.
I've read the thread on here for the 1.8t mk4 golf agu engine and seems the way Il probably go,
ide like to know if other engine codes i.e auq aum are the same or different fitment wise and what is the best one to go for apart from the apx/bam route, also would it be best to buy a whole car or purchase in parts as I know the gearbox will be no good and adjustments will have to be made for brakes ect? any help would be very much appreciated

Personally I'd buy a whole car,
An employee from my local euro car parts just sold a complete Leon Cupra R with a fuel oil pump for 800

You can also pick up an mk1 octavia vrs with about 140k on it for 1k easy

If you are going to fully service the lump anyyway then the mileage doesnt matter

That way you get the engine, turbo, ecu, intercooler, wiring loom and all then little bits that you'll struggle to source unless you have a doner vehicle

I thought buying a while car might be better, any advice on which route to go down ie engine codes for the mk4 golf? or going away from the vw would a supra,tt,a3 all be just as easy/hard to fit,
I'm looking for a easier job with best performance potential if that's possible
thanks

All you really need is engine, ancillaries, box, loom, ecu, shifter, from a donor vehicle. 

Mine was from an Audi A3. 

Just realised how bad my post was, should of said faulty oil pump.

Depending on what you buy to start with you may be able to break the rest of the car and make money back

All depends on space I guess

Or g60