I figured someone with a 48 woulda been on this one already. ohwell I don't know if your 48 is exactly the same as my 38 but mine will require removing the vent assembly to facilitate cleaning off the old gasket remains and installing the new one. If yours allows enough access to scrape out & clean the mounting surface without removing the vent assy. you might be able to drop the new gasket in some boiling water to soften & stretch it over the vent. If that works you'll need to let it cool & dry before sticking it down. I'm not recomending that, I've not done that. It just seems like it "might" work.

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