Hi Peter!
Welcome to the family and hope you get a lot of enjoyment out of your Pantera.
Generally, you will want everything to work well together - not too much in any one area. In example, too much carb or cam will not make a happy motor. So, intake/carb, cam, heads, exhaust all need to work together.
I would guess cam duration of aroun 240 +- 10 degrees and .5 or .6 lift. Dan Jones spec-ed my new cam and I am very happy with my new motor. Your motor sounds pretty close to what I have: 10:1 compression, same heads, headers, dual plane intake with a 750ish vacuum secondary carb.
I'm sure there are others around with some experience to make suggestions.
Have fun, be safe!
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