Ar10 gas port/buffer tuning guide?

Hi all, im looking to build a 7.5 inch .308 ar10 for the sole purpose of being stupid/punishing to various components. No need to tell me its dumb, I'm aware. I would like it to function perfectly fine unsuppressed, and not be enormously gassy suppressed.

I recognize this is a lofty goal, so im happy to get a heavy buffer and give it a lil extra gas for unsuppressed, and then just hope that the extra mass of the buffer slows up the opening of the bcg a bit when suppressed. I recognize i will not achieve perfection, im just looking to achieve some better results that slapping random components together and hoping for decent results.

Heres the kicker, I can't use an adjustable gas block on this build because one of the components I will be torturing is a fixed gas block.

So with that in mind, does anyone have suggestions for gas port size, buffer combos for a pistol gas 7.5 inch .308 ar10?