1.) Dual walbros
2.) Any TBE exhaust will do fine but definately get rid of any cats and I suggest installing some sort of cut out after the DP. I dont know the size of a Perrin FMIC but I would say get the biggest that you can
3.) Definately reverse intake manifold and port match it to your TGV's and anything else
4.)Dont know the answer as I like my boxer rumble
5.)I believe going to a stand alone will help with injectors that size. I hear the Hydra is quite nice and that is what the local is running with his insane 40r set up.