Question about handling damage from a leak.

We recently purchased a '77 Overlander that was basically a time capsule. The first rainstorm after our pulling it home showed a wet spot on the floor. We pulled up the linoleum and found wood rot and corrosion in that area. Wood rot has been removed and will be replaced, sealant has been purchased to start working on the seams and windows. The water has been running down inside the wall and my concern is can we seal the seams hopefully eliminating the leak and replace the floor without ripping out the walls? Will it dry out after leaks are sealed if we wait a bit to replace the subfloor in that area? Also is Silflex an adequate substitute for Vulkem if that is all we have available to us at this time? Yes, we are trying to avoid a huge remodel. Any advice is appreciated.