The Magic words,
It's bracket car, weighing 2700 lbs. and appearently on alcohol, IMO the heads are way too small for the most performance out of a 632" motor, but if you already have the heads and intake combo, i would use them unless you have unlimited funds or you are trying to be king of the hill.
__________________________________________________ ___________
I just put together a 476" motor with Brobix 2 plus heads @ 13 to 1 it ran 10.401 @ 128 mph in a 3700 lb car on the 5th pass down the track. The heads are fully ported and on gas 1050 dom.
The cam i think is way too small, the cam i used was a .722 lift. I think you need to be around .760/.780 if you have the converter to handle it.
Kinda funny you mention Holden, i have an Austrailan friend living in Michigan (USA) who has a 1969 holden, who i have sold and bought a few parts from. The car is kind of a cross between a Nova and a Pontiac, but totally different.
JMO
Zip.