Okay, I have reached the Calculator lair, and am ready to finish things, but...for some reason it won't let me just shoot the brains into nothing like it should, and I only have enough explosives available to destroy seven out of the eight cause my trap guy, Stumpy, won't just drop into the pits containing the last three brains so I can drop a single explosive right up next to them! Pretty sure this is a nasty glitch, and would love any help fixing it, cause I really, really, really don't want to start Cheyenne mountain all over again from scratch just to make sure I have enough explosives on hand to finish the job.

Try making collateral damages with a burst weapon (aim the weapon just to a side of the brain to hit it with the burst).

It worked, thank you so much!