I hope not as that is plain daft and will only end in tears. 
Couldnt agree more. With labour cost, parts, time etc, in the end it will be cheaper to sell his car and buy a gti and save for the insurance.
But if thats what he wants to do then good luck, it'll be a good project. I cant say that when i was younger i didn't think about doing the same with cars ive had, but i just couldn't justify the risk of doing it if i got pulled and had the car crushed for void insurance, not to mention if i hit someone, or my car got stolen, i mean how would you explain it to the insurance company if it got recovered.
"Hi there sir, we've recovered your car, only its registered as a 1.6, and this seems to have a 1.8t in it"
"yes the thieves must have stolen it, thought it was a bit of a flat turd and swapped the engine for a quick get away" - i think not
