Interesting suggestion. I bumped the capacitance up on cap #11 by 100pF and that got me right down to 550 kHz.
I'm curious now to try drying out the coils as suggested and see if the presets drift any.
Meanwhile, I'm moving on the the cabinet. The only really issue it has is crummy decals.
I'm very carefully sanding off the old ones, then I'll give the whole cabinet a light 320 grit sanding. Next, a little Howard's walnut ARF to refresh the color a bit.
Then apply the repro. decals and, finally, give it a few coats of fresh lacquer.
