I put one of the Hi Rev 7500 boxes from Ehrenberg on my 71 Demon 340 that RRR references above. Seems to be fine but I keep a spare in the car "just in case." It had an old Chrome box but after sitting for 25 years, it seems the chrome box oozed it's guts out into the box it was stored in forcing me to find another.
My avatar 408 car has a very old MSD 6AL box that seems to work fine I've unintentionally hit 7000+ rpm with it and the box seems to keep up fine.
