Do you happen to have a picture of the mounting plate you talk about below? I am about to get into this project and will end up with a Bendix unit so I would really like to see what this plate looks like.
If you do decide to get a bendix, make sure the rear mounting plate is included. These are offered both way, No Plate (cheaper), and with a Tack welded on plate.
A Bendix booster without the plate is a door stop.