crenwelge writes, "It is often that people buy an auxiliary only with no linkage and then have problems finding linkage."
Ah shoot, shifter is the easiest part of a retro-fit. I bought a used Hurst 4 speed shifter off Ebay, just the shifter mechanism, no lever nor rods. Perfect for an old Brown-Lipe transmission. Easy to fabricate mounts, easy to adapt on an old SM420 shift lever. Shifts rods are fabricated out of 3/8 inch rod lengths.
However, you do need an acetylene - oxygen welder or access to one, to make those adaptations. Bit of time, fun work, easy to do. Only requires good measuring and good planning.
Big bolt trucks have a perfect place for hanging a Brown-Lipe, right where the driveshaft is split. Always a healthy cross member there you can build upon. Hang the Brownie so the rear section of the driveshaft fits right, have the horizontal front section shorten to length.
Few days work, you are ready for the Daytona 500; got that overdrive! I declare, you can get your truck up to 55 miles per hour!
Billyray