Not to negate all your work and ideas, but there is an easier way. Shehadehd has made one for $200 that is simple plug and play and it has the service mode option built in and it operates on the go until about 20 MPH.
http://986forum.com/forums/general-discussions/51527-all-new-comfort-top-6.html
He says that currently he can only ship limited numbers, so if you want one, get hold of him.
Tony