Both have out-of-spec locking blocks. I tried to put the stainless slide on the blue/gold frame, since this would be a "complete" firearm until other parts arrive. Wouldn't fit (rails are too wide). Put the locking block in the grey frame to test that one. Same problem. Pulled the slide off an existing, functional Polymer 80 build to make sure the slide isn't the problem. That slide won't go on either locking block, despite being functional on an older Polymer 80.
So, would you contact Polymer 80 about the locking blocks, or just take a file and sandpaper to the rails until the slides fit? I already have a trouble ticket in with them for my 10mm build with an out-of-spec locking block. Will two more tickets make them think I'm just an idiot who doesn't know how to assemble a pistol? I've done several Polymer 80 builds that were flawless, and I'm used to doing a lot more involved work on 80% AR builds.