It seems like most sanctioning bodies limit is 10.5 wide for NSS classes, wider for FX classes. Unless you've got lots of money, trying different tires is prohibitive so you want to get it right the first time. You might be lucky enough to have friends with different tires that you can try. My 64 (NSS /B, 10.50 index) does not have any tub work so I went with the Hoosier 30X9, 92.5 circumference radial slick. I went that way solely on the recommendation of a good friend that has a legal SS 64 Plymouth and has raced it forever and with whom I have great respect for. He was right. I don't race much. I race mostly at Mopar events but they are at different tracks, at different times of the season. I have never had issues with traction regardless of the weather or track conditions. I like running higher tire pressure than bias slicks, car seems more stable. But, as they say, "results may vary". Any tire cannot stand alone as a comparison. Suspension, gearing, weight distribution and other factors that contribute to the overall "combination" of your specific car will determine the outcome.
Post some pics and good luck.
View attachment 388733