The info on the threads can be found in the "Pneumatic Manual for FIRST 2002 Competition" that was furnished in the kit.
The 2" cylinder uses 1-1/4" - 12 UNF for the mounting points at the nose and pivot end.
The Rod uses 1/2 - 20 UNF.
A 1-1/4" - 12 UNF Tap is expensive. It may be better to bore a clearence hole and use a 1-1/4" - 12 UNF nut.
(we need smiles of various stages of sleep deprivation)