FWIW, I did my front tank this fall, and I could not do it without dropping the tank. I'd heard some say that it's possible, and others say that it wasn't. I could get the retainer ring off, but my fuel lines have some funky bends in them to get the pick up down to the absolute bottom of the tank, and there wasn't enough room between the tank and the bed to be able to fish them out of there. Maybe if I had taken the fuel lines off the cap, but I didn't want to disturb anything that I didn't have to for fear that I'd end up having to replace something that wasn't readily available. I needed the truck to run that evening. I ran the tank almost empty (1/4) and then drained most of the rest into a 5 gal bucket using a piece of 3/8 ID rubber hose. Used a suction gun to fill the line, then just siphoned off another 3 gal. That made it light enough for me to maneuver by myself without too much problem. I used a couple of 2x4 blocks to block up one end while I positioned the other end and got the bolts started. I'm going to have to do it again because the line that I put back on is too long and isn't sitting in the correct spot in the tank, and I still have to do the rear anyway. I didn't have an old pick up line to use as a reference. It took me about 3 hours including a trip down to the hardware store for some aluminum screen, and then to the auto parts store for the fuel line and some clamps. That was using a combination wrench and a ratchet. An impact would have made it a LOT easier. I'll have one before I tear into the rest of it. With an impact and the parts laying in the truck, I could have probably done it in an hour. Taking the bed off would be easier, but I have to do it all on my own in the drive way so that's probably not a good option for me.
Just my 2 bits,
Mark
