Hy Shellology, I succesfully installed a dual master cylinder/booster into a 52 3800, I had to trim the parking brake band a little bit for clearance. I had to modify the supplied mounting bracket [ it wouldn't have fit anyway ]. I also put the same type of setup in a 47 1/2 ton panel with a 3 spd., I had to modify that mounting bracket as well, those brackets don't seem to be very well designed, hope that helps.
