Update.
Two trips to the welding shop and I now have a modified master cylinder bracket with a plate to mount the proprotioning valve. Pictures are buried in this album.

http://s241.photobucket.com/albums/ff93/jal12147/1951%20Chevrolet%20Pick%20up/

I've ordered a brake line kit and plan to use the stock brake line routing. Everything from the tee fitting forward and rearward on the passenger side. I also ordered 2 L fittings so I'll only have to fabricate lines from the master to the proportioning valve and from the valve to the two L fittings on the passenger side of the truck (one connected to the line for the rear and one for the line to the new disc brakes in the front.)
Unfortunately I didn't take any pictures of the bracket before I had it modified but it is from CPP to fit 47-54 Chev trucks and some form of F**d. Some height was added to the side that bolts to the frame so the bolt holes could be relocated 3/4" higher, 5/8" was added to the bottom with with a horizontal plate to mount the proportioning valve.

John
Milford, MI
1951 Chevrolet 3100
1975 Delta 88 convertible