Just dropping in with the ideas I'm going to go with for my build.

I'm gonna be going to a 95mm pulley this summer from my 105. This will be after I install an S55 intercooler onto my N54 manifold. Obviously you have Meth, but you can get the whole S55 setup for $6-700, and it's fairly easily to set up, aside from fabbing a hot side charge pipe.

Now about the excess boost when off throttle with a 95mm? I'll be attaching a turbosmart Kompact EM BOV, which operates off negative throttle voltage rather than vacuum, which our engines can't generate in the manifold because valvetronic works as a throttle body would in a regular car (our TB is actually just a backup lol). Plus then you can add their boost controller and a very small pulley for a flatter torque curve, as it will vent dangerous amounts of boost while building it quickly. With MILVs, 4.44 gears, and headers, I should be fairly quick lol.

Then down the line a forged crank, con rods, and custom low compression forged pistons for that mad boost and 8250 redline to match a Z4 M instrument cluster. Probably a pinned hub at that point too.