Something I didn't know about until my engine builder friend told me to do, on the engine he built for me in the early 80's....
Aluminum intakes need to be retorqued one or more times after initial installation. Aluminum expands and contracts way more than iron. After the first few times the engine has warmed up to temp, and cooled back down, the gaskets get compressed, but upon cooling down, leaves the bolts loose, not the same w/ iron.
So after running engine through it's heating/cooling cycle, maybe 10-12 times check torque ONLY after engine has cooled ALL the way back down to the temp of the air...
So post 18 the loosening/tightening shouldn't have been a problem. Hope you didn't cut that divider out...
