[Tmend]

I have bought the NOS 10ohm speakers you speak of. I learned that blazer speakers are their own breed. The blazer 10ohm speakers 4 holes are different. They are threaded. You can always thread the others but would require you to use a thicker screw thus having also to make the speaker grill holes bigger. The original blazer screws go right through the reg 10ohm 4x10 speakers. That’s what I encountered if someone has diff experience please chime in.