So I rebuilt my carb and was putting it all back together (down to <30 minutes to finish) and I think I dropped one of the screws down into one of the cylinders. Couldn't reach anything sticking my fingers down the intakes, so trying to take the cover off the heads to look inside. Undid all the screws thougha and it doesn't seem to come off as I'd expect. Is there some sort of trick to this? Mind you other than technical aptitude, I have zero experience with going any further than my carb. Any ideas are appreciated...