Bill's right, I forgot that. Sit in the car. Strap in. With a helmet on. Make sure you can reach and see everything. Can you shift? Are the pedals in a good spot? And stay there for a while. Like 5 minutes. Are you comfortable? Can you get in and out easily?
There are two styles of dragster seating, one more upright and one more "laid back". I can't stand the laid back style, mostly because I'm big and with a helmet on I can't see things as well. But some people love it. A matter of taste.
Don't rush this part. Looking cool is one thing, winning is more fun and that requires being comfortable.