[tamax]

Do not go with 6X heads unless you are looking too save on gas mileage the CC's of the combustion chamber are so big. Even if u cut them down you wont get the HP you are looking for 7J2's are not a common # either. If you are looking for some HP in a head thats more easily found, pick up a set of # 62's off of 400/428's from the late 60's and into 1970. Your combo will be fine, wont be a world beater but most vehicles will still be in your rearview after launch. What stall are you running on your converter for that cam, cuz it will need about a 2800-3500 for best performance.