Hello all. I just bought a '92 940 turbo and it's got a 4speed with overdrive which works fine.. however i am looking into possibly doing some modifications to squeeze some more power out of the engine. Is this gearbox suitable for any significant power gains? I seem to read that m90(?) is the gearbox of choice... but i am pretty clueless so any help here would be appriciated. Also how hard is the gearbox swap? Bearing in mind i am only just starting working on cars. Thanks, =)