I wish I could keep this level of progress for the rest of the restoration but expect things to slow down after this.
You can get reels of 2" tape for not too much if you shop around. I should have a reel of 456 at my door tomorrow in fact that cost $50 shipped albeit it will need a bake.
The red wiring of that guage seems to be related to the drum motors. As I was desoldering the cabling and not clipping them I can only assume this is some relic of some form of conversion or something. Indeed I'll need the manual to know for certain.
Anyways, I was able to strip the drum down almost completely after I pulled out the calipers and micrometer. Having learned a lot from the DVK-2400 restoration I measured and marked down everything before it was removed. The result is below.
The two halves of the drum are press fit and pinned so you won't be able to split it in half or otherwise spin it to clean it up that way. The other problem is that each of the tape guides have small up/down adjustments. Without a proper jig there's no way in all hell I'm going to touch any of them so here we are now. HMMMMMMM....
One idea is that because emery paper is available with a 1" width I can thread it like a piece of tape and clean up the path like that and do the same to polish it. Outside of the path however and around the guides I'm not entirely sure how to do it without possibly marring the surface pretty bad but it needs to be cleaned up or else the corrosion might creep right back into the tape path. We cannot use solvent batch because of both the potted head coil and all my reference marks.