I had to do my 91 a couple times.
I
did get the filler hose off one end or the other - can't remember which right now. It definitely is difficult to pull it off. Pretty sure I got it off the filler neck and left the other end attached to tank? Yeah, because I stuck a siphon hose directly down the hose to empty the tank.
As for the fuel lines, I loosened the straps and dropped the tank down a few inches. Might have to support the tank with jack, blocks, or a strap running from a frame crossmember near the axle and back to the trailer hitch. Anyway then I could with some difficulty reach in over the frame from the left wheel well and loosen the gas lines (TBI) with an open end wrench. Just takes patience as you can only turn about 1/8 turn at a time.
On mine it was a trick getting to clear the tailpipe and hangar, and of course after that you have to slide the tank sideways to left/driver to get the fill hose clear of the frame.
If you're replacing the tank
and fill hose then you could just cut the darn thing
Putting it back in, I used the aforementioned strap to support and lift the tank until I could get the fuel lines and mounting straps connected. I just used a tow strap, hook on one end to the frame above the axle, under the tank, and then a half hitch around the trailer ball. I had my wife taking up the "belay" as I lifted and guided the tank from below.
I had the rear wheels up on my ramp timbers for more clearance.