That is the worst idea I have heard in a while. 1.8t's and manual boost controllers don't like each other very much. There was a guy who asked about putting a MBC on his 1.8t in this forum. Everyone said "don't do it", but he did it anyway, the car went into limp mode and he had all kinds off problems. The easiest way to up the boost without major issues, is to get some aftermarket software either from APR, Revo, Giac, Etc.