not much fabbing, i used the mk3 dash mounts and welded them to the mk4 support so it is completely bolt in. The only other fab that I can remember is i needed to use both mk3 and mk4 steering assembly. The way it sits now the dash could be taken out and put in any mk3. The door cards still need to be narrowed at the point where they touch the dash, everything fits nice but i’m sure there will be small bugs that i will need to work out however.