I finished blasting and painting the frame rails and undercoating the underside along with installing a new gas tank. This is on my 89 S15 Jimmy.

Rear Frame Rail

 

Wow!! That looks nice! You obviously took off a lot of hardware like the fuel lines to do it right!

 

I took off the fuel lines, the brake line, the Ebrake cable on the drivers side and removed the mounting bracket for the Cat on the passenger side.. I was able to blast and paint the frame rails without any problem. I blasted and painted the inside and outside of the framerails in two operations. All very time consuming. I sanded and clear coated the fuel and brake lines. If I was really smart I would have done all the rust mitigation and undercoating while I had the engine and trans removed. But I was not going to get into all that yet. But the fuel pump was dead I had to remove tank and the rear frame cross members were rusted, I went down a rabbit hole with getting a new tank, Installing Rivnuts for the tank cover. Removing the leaf springs and shocks. I started out with 3M Spray can undercoating but I had a shutz gun and wanted to give it shot.using the 3M Body SHutz Undercoating. I ended up using 2 bottles. (Expensive though) I am finally to the point of putting things back together again.

 

Wow, a lot of work but it looks great and should give you plenty of peace of mind regarding potential rust.

 

Thanks. This whole job has been a rabbit hole. Started out with Oil Pan Gasket replacement. Went on to removing the engine and trans, Installing camshaft, 94 Heads, roller rockers with 1.51 ratio, new timing gear set, Edelbrock NOS Valve Covers, Hand bent new fuel line from the TBI to eliminate kinks by adding a TBI adapter with fuel pressure gage, Swaged new fuel line to mate with old fuel line and silver brazed the joint, Painting the firewall, the hood, inner fenders, Outer Fenders. Painting all the hardware. New Ebrake cable from the brake pedal to the equalizer. Installed rivnouts to replace sheet metal scews for the vent grill and most of the sheet metal screw grounds. The Rivnuts eliminate sheet metal screws from stripping out the sheetmetal. This could have easily been a project that had good intentions but never finished. I can see the light at the end of the tunnel. I also have a chip for the edelbrock camshaft installed in the computer. I had to replace the ignition module for no spark condition, I had to replace the fuel pump for not turning on. I am going to finish as much as I can before I add fuel and try to start.