Mossberg forend nut

[Gasman91]

I’ve got a Mossberg 7-3/4” action slide assemble that I cannot for the life of me get the nut loose on. I’ve ordered a new slide assembly and nut to get the new forend installed, but would like to disassemble the old one to either keep as a spare or maybe sell. Anyone have any tricks to getting the dang thing off? Yes the factory plastic forend is still on it, and not I am now worried damaging it.