i know about the head gasket problems but i know of a 1.4 zr that got turbo'd running 160bhp @ 4psi and thats been going strong for a few years now.
the main reason that head gaskets go on rovers/mg's is that people dint let them warm up properly.
as for the idea of sticking a mini engine in it, that could be good, but if i was to stick a new engine in then it would be the t16 out of the old rover coupes (2litre turbo) as thats pretty much a straight swap, so i could do that myself
any more info anyone might have to help me with supercharging it would be greatly appreciated