If you have an 83, then assuming it is a metal roof. And is it bumpy metal or flat and smooth?
For a sound waterproof repair on flat smooth metal covering over a 3" hole, they sell Eternabond sealant tape. In various widths. EternaBond
It is used on rubber roofs but it does adhere to metal well as I have used in on aluminum edging. There is however no support in the open hole area. If you go this route I would suggest some how filling the hole with sheet metal or something as the E bond has no support structure to it.
I say smooth roof as the E bond will adhere well to the flat. If you have a bumpy metal finish, it will stick but the little air spaces in the bumps may present a problem of total bonding.
If you use the E bond, make 110% sure to read directions on prepping the surface super clean first. The wrong prep and it will not correctly adhere.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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