I'm unaware of a second by second combat rule-set for SM. However, Privateers and Firearms Law provide an excellent rule-set that you can adjust easily to RM2 combat.
Since all the special attacks are listed as %'s, (a "double tap" is a mnv that uses XX to XX activity and allows the shooter to attack the target twice) you should be able to convert them to your CEATS like system with appropriate experimentation.
Good luck. I hope to hear more about this game. Sounds fun.