Been running the 8563 billet with the 6AL box on my 69 400 for a long time with no real issues other than the dist will get all rusty and corroded after ten years or so, even though it's very dry here. (I live in southern Arizona). This seems to be an even bigger issue these days from what I've read online. Some people won't even buy MSD anymore. I'm at that point again and wondering if I can run a different distributor with the 6AL box? Will the connection between the two be the same? I know that cutting and reworking that connection is kind of a no no. Debating whether to pull it all out and run the HEI setup. All comments are very much appreciated.

Not sure about the 6AL, but I'm running the 6A with an HEI and MSD blaster coil.

Appreciate the response Dr... Little confused though. Isn't running an outboard coil and box a little redundant on a HEI? I thought that was the whole idea behind the hei, so the box and coil were part of the distributor? Maybe I'm wrong...I was just wondering (for example) if a Petronix dist would work with the MSD box ? Tired of buying MSD dist"s. They are too expensive. Thank you.

The MSD box just takes the place of your ignition module, not the coil.
Here's an illustration.

Dont belive everything you read on the internet
I have been running a 6AL box in my cars since 1990. they last longer inside the car verses in the engine compartment. had them hooked up to stock points destributors to HEI and MSD pro billet distributors without any problems.
Changing the wiring to the distributor and coil isnt really a big deal.

X2, my 6A box has been on my firewall for almost 20 years and hasn't skipped a beat. Maybe the build quality has gone done in recent years? Wonder where they are being made now?

I've never had a problem with the box. It's the distributors that get rusty and corroded on the inside. It's happened to me twice, so I know it's not a wives tale. I rebuilt this 69 about 25 years ago. The box is fine. The first distributor lasted about 18 years and about 30k miles, before it went to hell. (I'd say that is pretty good). The second lasted less than half that time. That is what some people (not everyone) were commenting about online... I want to continue using the box if I can. I just would like to try another brand dist to see if they last any longer. Thanks for your input.

Just go to a parts store and tell them you want a remanf. HEI distributor for a 74 Pontiac 400, that's the one I've been using, a lot cheaper then getting an aftermarket shiny unit that you can't even see stuffed back up against the firewall.