The speaker cone had some tears in it, including a 1 1/2" long tear along the outside edge which created an audible flapping noise at high output. The others were small punctures, also in the edge of the speaker cone.

Since there was no missing material and the fibers could still mesh across the tears, I mixed 3:1 Aleene's Tacky Glue and water and brushed it on.

I then set aside the speaker to dry and started removing the remaining chassis hardware from the cabinet. The handle and corners are reusable, but the rubber feet are dry, cracked, and falling apart. I believe I have some spare amp feet somewhere to replace them.

The last part to remove was the back panel, held on with two screws. The last screw in the panel, the last screw to remove on the entire amp, and it was the first and only one to strip during the entire tear down process. I got it off with vice grips.

With the amp fully apart, the next step was to peel off the tolex and prepare to re-cover the amp. It didn't go that smoothly.

Underneath the tolex was a thick layer of glue and the remains of the original black carpeting. What's worse, in large swaths the rubber delaminated from the fiber mesh backing, leaving yet another layer of fiber embedded in the glue.

After the tolex was removed, I attempted to sand, file, and chisel the gunk off of the amp, but to no avail, it was just stuck on too well.

I also noted that one of the side panels had come unglued and was only held on with finishing nails. Besides fixing that, I'd like the grill cloth to wrap around the front panel for a cleaner edge, and it would be nice if the panel was removable. Lastly, the plywood has voids in several places. As a result, I plan to deconstruct the box and re-cut the panels out of some fresh scrap plywood.

Here's the dried speaker repair:

It seems to have fixed the flapping sound. The amp sounds overdrive-heavy at the moment, but in my experience that seems to clear itself up when the speaker is mounted properly.