Talk to Pittsburgh racer, he's a friendly guy and he ports his own heads. But you said yourself that you have valve train issues. Maybe start there. Springs don't cost that much. What's your performance goal?
My 9.70’s are in a car weighing only 2860 so it’s not a heavyweight, not a lite weight. That set of Edelbrock heads has the pushrod in the stock location but I used about ever available millimeter to do it. If this was a test n tune go for a balls out number I sure as heck wouldn’t have a powerglide and 14-32 tires on it. I would have a 904 and 10 inch radials. These 9.70’s were also at Keystone in the Summer. Not some coastal super-track. Bracket cars need repeatability