Right, I saw your setup in the links tamo3 posted and it looked pretty good and I am seriously considering that route (since my welding skills are less than ideal). I work in an aircraft research facility at the University of Iowa and had some engineers look at my drawings for my idea, they said it should work as long as I put spacers in between the mounting ears in tunnel to keep it rigid and transfer shear through the bolts without introducing horizontal rotation along the front to back line of the car. Since I have the stuff already made up for my adapter plate and spacers, I am going to try the no cut method first. I will watch it for any deformation in the adapter plate and the mounting ears over the first couple of months, if I see any signs of trouble I will change it to what you did. What I am most worried about it up and down deformation of the adapter plate, most of the weight of the mount is on the transmission case, but a little is cantilevered out past it with my setup.
How is your setup holding up? I assume it is pretty solid.