I think I want to cut the quarter panel off

[SteveMcqueenRules]

I don't want to but I think I might need to cut off the quarter panel to be able to see what going on inside and since I need to fix the wheel house anyways. There is rust through on the quarter itself only around the wheel lip. But since it has rust out around the rear window channel and in the trunk and wheel housing I figure there might be more lurking where I cant see
What do you think should I cut off the quarter or just fix it and the wheel housing and POR-15 all the hard to get at spots?
I would weld this same quarter back on after fixing it. Also keep in mind they don't make new quarters for these cars.