Do you have a T-100? It's certainly not essential, but is a treat to use, and makes the wow-n-flutter tapes work as they should (with tactile feedback, for troubleshooting).
The head alignment guage is, unfortunately, absolutely essential. As the classic Nak's age their pinch roller arm pivots' lubricants become more wax than grease, and will bind up solid. The only real solution is to pry 'em out, wash the pivots in alcohol (a little bit for Santa Claus, a little for the reindeer, a little more for Santa Claus, etc.) and relube.
So you'll need the head alignment guage to set head "height". There's no practical substitute, AFAIK.
You may be surprised to find The Nak Official Test Tapes labeled "Teac", but this wasn't at all a bad thing back then. They made the best.
Have you found suitable sources of replacement rubber? That's the critical issue.
I have all the Nak widgets needed for proper restorations, and have been retired from the gig for several years. Not the kinda guy to sell tools to "collectors" on eBay, I'd be interested in finding a good home where they'll feel loved and appreciated. And used.
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