Well I leapt before I looked! Seems like the first coat on the smaller box revealed some shortcoming in the prep. A bit thin in spots, surface imperfections showing through, and overall not very much gloss. Not a deal killer - sometimes you gotta go over spots again. So I'll have hit it with some 320 grit paper and reshoot. I'll take some more prep time with the large box and see if I can minimize the mistakes.
There's some greasy residue on the inside of the big box so I need to de-grease with acetone, then sand, then wipe dust free with some more acetone.