I think front and rear
windows are just pieces of plexiglass set in a rubber gasket. If not, maybe a picture to clarify what you’re dealing with?
Given the difficulty of getting fixed plexiglass windows in and out, I’d be inclined to cut new plexiglass along with a fresh seal. As long as they’re not cracked or crazed, they’re still good, but as they tend to scratch and discolor over time, might as well start fresh. Use the old as a template.
I’ve never done it, but there are old threads and maybe a YouTube on how to R&R the plexiglass windows. Did I say it’s tricky?