What are the correct AC Delco plugs to run in aluminum "MA" heads?

[trick86]

Looking for some input on which AC Delco plugs to run in aluminum "MA" heads? The set up is 17 psi on 94 octane(heat range input). Looking for the equalivlant to running R43TS's in a stock heads. Here are some AC Delco part numbers that could work for referance-FR3LS, FR3LS6, FR2LS, 41-603, FR3LSJ, FR4LSJ, FR5LS. Which ones the trick ticket?
Thanks

 

[Mike Licht]

FR3-LS would be a good place to start. We used to use the FR1-LS for race but those are cold