Ok, both tweeters and both midranges in place and bolted up with final socket-head bolts.

Why did I think it was a good idea to use all 8 holes for each woofer?! I've had a few incidents of 5-6 bolts going in and then a Tee-nut gets pushed off. Now I have a new technique of putting all 8 bolts through the driver chassis holes and offering them all up to the holes, 'snagging' each bolt into the thread very gently. Once I've achieved that, I can tighten them up safely. One woofer in, three to go...

You need patience for a job like this. No rushing.