Definitly having the bed out of the way makes thing way easier, but it can be done with the bed in place. I pulled a tank out of a truck while the bed was still in place and it seemed not really difficult. I did pull off the fuel fill hose to siphon the fuel out though. There is a ground wire that attaches to the frame that I snipped off, because it's bolt was hard to get too. That was all the butchery that I did in the removal though. Definitly you would want to install new fuel lines onto the fuel pick up/sending unit assy before the tank was reinstalled, because there is not much vertical room to work with between the top of the tank and bottom of the bed, with a bed installed. Just be shure to lable the hoses so you know where to attach them. Some trucks have two hose fittings on the fuel pick up/sending unit and some have three and some like the CUCV's have three with one capped off. I haven't figured out the ryme or reason for this yet, but I will pretty soon as I want to bolt down the bed on the truck that I'm fixing up. I also have not addressed the issue of installing the wiring for the fuel tank switch yet. I am Crew Cab rich right now as I have three, too bad the one I want to fix up is the one with the single tank

, so that is something I will eventually get to as I want to install an aux fuel tank into an M1008 as well and have a factory style operation with the tank switch and fuel gauge function. I may be going up to where I keep my "Gems" tomorrow. I can snap some fotos then.