teach me about subaru conversions .

Hello all. I'm posting this for my gaffa he's building a hill climb car based on a vw beetle pan ( swing axel) and is wanting to go down the Subaru route . .. help. I've been looking on the forum and I'm lost so I thought it better to just ask . So basically its a clean slate aircooled engine out ,where to start .he wants a turbo motor not a n/a its kind of a budget build so dident just want to got buy every thing ( altho it would make life easier) so he's planning on getting a full running and driveing car and stripping for engine loom that sort of thing , but what to go for buy not buy engine type wise pit falls help info what you people have used where from any help realy will be great . Il post up pics of the car also so you can see how it builds

Thanks in advance Jim