"I touched the rubber part of the sender and the whole piece just broke off from the tank"
You may find the tubes are also badly rusted. Vacuum/brush away the dirt and apply some rust proofing or similar to slow further rusting.

"When I do decide to fix this, how difficult will it be, can I repair it from the access hatch or is a tank drop necessary???? "
No need to drop tank.

Because you're working around gas you won't be able to repair using solder. If crimping/splicing can't be done then you'll need to pull the pump. (Remove bung nut using a non-sparking eg. copper pipe flattened at one end, to turn it, and lift pump out.) If the tubes are badly rusted they may snap on you so unless you want to repair those, you'll need a new pump.

Unfortunately, disconnecting the lines to the pump will probably require cutting the nylon fuel line, thus opening another problem of finding replacements. There's a post presently on about this. See "Urban Legend"

With the pump out you'll be able to repair the wire.


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1980 245 Canadian B21A with SU carb and M46 trans