Its a different kettle of fish, hundreds of people have fitted VR6's + there are plenty of written guides and stripping simple engines like the Golf GTi
1.8 8v is childs play. Boreing out a block is nothing more than accurately clamping an engine block and drilling it out slowly, i've watched a couple of engines being done and the machine pretty much does it on its own much like the machines used for skimming a head.I havn't given a 205 intercooler any thought and it would depend very much upon the size of the intercooler and the space available in order to do the work which would require re-jiggleing (technical term there) of the radiator, slam planel and front bumper.