TM2C, I had heard about using those side tanks, and have been planning to go to the dismantler and look for one to complete a two-tank setup. I have a junker '74 in the back yard, but it's a long bed and the tanks are WAY too long. So...just got back from the dismantler with a short bed tank, and it looks like it will work in the 3/4 ton frame. BTW, these tanks are the same left and right. Filler necks are different. Now I get to engineer another fill setup, working around the side-mount spare.
I looked at a couple of late '70s Suburbans while I was there. Those tanks are just about square--maybe 26" by 26" or so. The 1/2 ton trucks must not have the crossmember between the rear spring hangers like the 3/4 ton trucks have. I only have about 17" between the crossmember and the back cover of the differential. I had to use a mallet to beat a depression in the front of the tank for clearance.
Joe
