I have trial fitted my servo kit today- I will take it apart to paint the adaptor plate.
I have welded the studs in, front and back of plate, then polished any raised weld flat.
I have drilled a very shallow counter sink in the m/c holes to clear the weld around the very base of the studs. Similarly I have shallow counter sunk the adaptor holes that face the servo studs to clear the raised rivet fixing of the stud base. Strangely this only affected the powder coated servos - all the zinc and Chrome servos were nice and flush.
It all fits very snugly in a Cabrio. There is plenty of clearance to the side.
The reservoir cap comes closest to the underside of the bonnnet, with around 5mm of clearance. But since the master cylinder is fixed, 5mm should be sufficient.