[Ron Ramirez]

Yes, the dial of a 60 is much smaller than the 620 dial. Besides, I'm not sure that the tuning shaft would fit properly. I no longer own a 60 or 620 so I can't measure.

620 chassis are not hard to find. Better yet, get a 630 chassis, remove its shadowmeter and bypass it with a 1000 ohm resistor. The 630 runs a higher B+ so it produces another watt or two of audio output.

I had a 630B with a rough cabinet, and an empty 610T "Big Bullet" cabinet. I now have a hybrid 610T with 630 chassis.