Here is the basic step by step.
1. Remove spare and spare hanger bar and bolts.
2. Grind rivet heads at frame rails and remove spare tire bracket.
3. Cut 1" notch in rear bed mount sill from inside frame rail to inside frame rail.
4. Test fit tank positioned as far to the rear as it will go. (LMC 21 Gallon kit) I had to cold bend the DS top frame rail a bit to clearance the filler neck.
5. I had to bend up the corners of the rear most frame cross brace as they touched the upper rear corners of the tank. Once bent up slightly, the tank slid fully rearward, its rear lip on the underside of the rear cross brace but no where else did the cross brace touch the tank. This positioning moved the DS center (1/2") vent tube out from under the bed cross sill that I notched. The vent then sat to the rear of the bed cross sill instead of under it, allowing me to attach a vent hose with no interference from the bed bolt that go's into the frame on the DS rear.
6. Mark and Drill 2 mounting holes in the underside of the frame rails for the DS and PS flange of the tank. Remove tank.
7. Install 3/8" bolts with lock washers under the bolt heads. Keeps the heads from turning as you snug up the nuts from the underside (tank eliminates access to the heads of these mounting bolts unless you add holes in the side of the frame to get a wrench on the bolt heads.)
8. Using a roll of new metal fuel line and some rubber hose and 4 band clamps, tie the two unneeded forward vent/return tubes together. Route the tube/line up and around the front of the tank.
9. Install a length of vent hose to the 1/2" vent on the center DS of the tank with a band clamp.
10. Install a length of 1.5" filler hose on the tank with two band clamps. (Remember, my fender fill neck is 1.5" and the tank filler neck is 1.375". Two clamps at the tank prevented leaks. If you prefer make the transition from 1.5" to 1.3" by installing a steel Exhaust reducer near the tank. ROL makes them in 1.5 to 1.375" transition. Then you can install that 1.5" hose at the fender filler and a length of 1.375 hose at the tank neck. But so far, mine has no leaks as two clamps seems to have cinched the 1.5" filler hose to the 1.375 tank filler neck quite nicely.)
11. Install the sending unit, its gasket and wire it up. Install a length of fuel filler hose to the sending unit with a band clamp.
12. Install the tank, fishing the filler/vent tubes up and between frame and bed. Then tighten up the four mounting bolts securing tank to frame. Tank lip is on the bottom edges of the DS and PS frame and on the bottom edge of the rearmost frame cross brace. Top of the tank does NOT touch the notched bed sill. On the DS side mount the ends of the aluminum tank straps on the tank flange mounting bolts. Use fender washers under the nuts.
13. Drill the PS outside face of the frame rail for the j-hooks, install and snug up the bolts to pull the tank straps tight across the bottom of the tank from DS to PS side. Use padding under the straps if you like. I did not and have no squeaks.
14. Ground the tank to the frame.
15. Fish the sending wire up into the cab and attach with solder to the original gas gauge line at the DS rear of the cab/door.
16. Pick a spot on the fender and drill a hole for the boat deck filler. Drill holes for the attaching screws. I used a stainless deck filler and #10 stainless screws and lock nuts and flat washers.
17. Install a 1.5" to 1.5" 90 degree exhaust elbow in the tank filler hose with a band clamp.
18. Notch the sheet metal of the DS bed (near the rear fender brace rod) as needed to clearance the 90 degree bend making the path to the tank at least level (i.e. don't have the elbow low so gas has to run up hill to the tank filler neck.) There is enough room to do this getting a level run and not removing the rear most fender brace.
19. Install a length of 1.5" filler hose between the top of the 90 degree elbow and the fender filler neck with band clamps
20. Install your choice of vent in the hose from the vent line of the tank, place the vent high in the fender well and point it down to keep out water. You can also place the vent behind the filler hose to keep water off.
21. Under the truck, use some screw in clips to secure the line you installed (to link the two unneeded returns together) up against the bottom of the bed....prevents vibration of the line.
22. Fish the new metal fuel line from tank to pump. Hook up both ends. Secure along the length of the inner PS frame using a combination of the factory fuel line clips and new clips every 12" or so to prevent fuel line vibration/cracking.
23. Put in 5 gallons of gas, check for leaks. Start the truck. Check for leaks. Go drive. Check for leaks. Fill up, drive, check for leaks.
24. Ensure dash gauge is working.
25. Remove cab bomb tank from behind seat and sell cheep or give it away.
26. Enjoy
Last edited by NeedsTires; 01/14/2015 2:47 PM.
