Best (affordable) setup back in the day for ATE was progressive springs/CC products top clamp, 7.5wt oil, and a fork brace, and bottoming springs can be made from the stock springs you'll have left over. Didn't get much better than that.
I have a buddy that' selling a CC top clamp if your interested, complete with trimmed headlight ears. Lemme know I'll hook you up.
I talked to Matt Wiley today about emulators. They make the emulators and matching springs for a complete kit. Best to call and find out which/what for the ATE's though. He said the website needs updating for the airheads. Very confusing otherwise.
Not to confuse the issue, but for the '81 Brembo forks I was told that the slack in the damper rod at the bottom between the piston and the circlip needs to be nil and is taken up by shims available (MAXBMW
The internals on the ATE are quite different, especially the damper assembly.
Best call Mr. Wiley and ask if you're going all out with the emulators.
I'd think the "Best (affordable)' is the best place to start.