So Im looking to buy another T42 to run a race tune on, can I buy any T42 and full flash whatever OS I want to run on it? I think so, but I just want to double check.

Looking at these part numbers:
24235340
24230461 (looks like this one is guaranteed to work with the TBSS)
24243901

Any preference? Any difference between them? Or just superseeding each other?

OS will be 24239924, cal 24236062 stock 08 TBSS OS at first then move to a car OS.

Thanks, I believe they are just like the E67/E38/LS1s that any OS can be flashed but I want to make sure before I spend the money.