It moves in fine with the rear brake tool (e-brake screw in - I’ve heard spec miata guys take the e-brake part out to reduce drag - thoughts?). I made sure to go new motorcraft. The parts store seals apparently cant handle track heat
If ebrake cable has slack, i can't see it pulling the pad in. Easy enough to disconnect the cable to try it tho. If no fix, reconnect it.
You could also do that for abs. Disconnect the sensor plug and see what it does. The stock abs module used to COOK my brakes on track when i ran slicks. Changing to 302s module fixed that. But if somehow abs is deing tripped and kicking the brake on, it could cause this. It could be a front sensor bad too that's giving a miscount of the reluctor wheel so the abs is activating the rear brake to correct a problem that's not really there.
Now that my abs problem is sorted, I have new calipers, pads and rotors going on. I already replaced the rear axle seals as they got cooked by the heat also. Probably going to swap front hubs too just as a safety item/ wear part/ cover my ass part. Then I should be good for a long time.
My caliper seals were fried, rotors cracked and warped from the excessive heat. The new stuff outta be quite pleasant!