If the instructions say “Put on the shim then the squealer”, make sure you’re not confusing the shim and the clip. If the instructions say “Remove the 12mm bolts nearest to the axle”, they are actually 14mm. If the instructions say “installation is the opposite of removal”, you best have a video of exactly how you removed everything.
Trying to swap pads and rotors on the Miata shouldn’t have been this difficult. The biggest issue was getting the pad (and clips) back into the caliper frame. I was confused as the instructions say you might need to move the shims and squealer from the old pads to the new pads. The shim is thin piece of metal that attaches to the back of the pad. My new pads had those, but did not come with a new squealer. The clips that hold the pads into the frame came out with the pads, so I confused those clips with the shims. The instructions had me trying to install the clip and pad as a single unit into the frame. My first good idea as to put the clips into the frame first then insert the pads.
Even with the clips pre-installed, I was getting the shim caught on the frame when trying to install the pad. I tried repeatedly until I realized the shim was getting caught on the inner side of both the top and bottom of the pad. Only then did I realize the pads were supposed to be inserted at a slight angle first (sort of like a memory module in a computer) and then snapped into place. That took another 20 minutes to figure out. Go me. Two hours later, one rotor and set of pads replaced, only three more sets to go!