[HWYSTR455]

If you want to ditch the MSD 6AL, there's nothing wrong with the Summit ready to run, and you save some coin:

https://www.summitracing.com/parts/s...w/make/Pontiac

Ditching the MSD box will simplify things, and not sure you will see much, if any, of a difference. That too you could recoup some expense if you sell it.

Yes, valley pan to intake, is that between the front and middle carb?

There should be a full time and/or ported vacuum port on the center carb, you can use whichever you prefer. I'm a full time port guy, but use whatever you feel comfortable with for now. And at the moment, that distributor does not have a vacuum advance, so adding one should help with drivability.

Do you have power brakes? Where is that hooked up?

I'm not that familiar with tripowers, but I'm sure it's easy to look up. Someone else may chime in too.

Yup, post a pic of the #1 spark plug. It's possible that there's a vacuum leak, or the center carb is a little lean. Lean would probably mean other cyls would show a diff temp too, but take a look at the plug first.

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