Why are you worried about other's races? You need to worry about your own car first.
You had months to get your car ready, and when it came time to lock it in, you said that you had a family problem to attend to. Now it sounds like you just weren't ready with your car, and that means that you made up a lie to not lock it in.
You wanted me to run a stock GTO without the spray vs your built GTO. That was dumb of you to even ask that. Now you want to take your built, gutted, sprayed, and slicked GTO and run a stock GTO?
You always told me not to run the spray on my Mustang to run against your GTO. Now, let's stick to that - no spray on either car, and we run the same tire (slicks or radials - your choice). Do you want to do this? Are you ready to lock it in?