i was changing my thermostat today, and the middle pressure screw on the housing fell and i cant find it, and the parts store told me that i needed to know the thread and other stuff, so can neone help me out cuz otherwise im screwed

If you have another car you can drive, Take the other half of the screw to the parts store.

the two are screws, and one is a pressure thing so it is different
so i need to find the exact one or give him the thread and **** like that

Wrecker. Get the screw, or the whole outlet. Virtually any 3800 from ALOT of years. Probably cost you a dollar.

it would be easier to just get the entire top.

Then he'd need a new gasket again

The screw takes just a screwdriver and maybe a crescent wrench to remove.

It'd almost be worth it to grab a flashlight and find the sucker. It'* probably behind a heat shield or something.