intake leak

Hey guys,
my 88GT has an eldlebrock performer RPM intake and I noticed two screws on the upper intake were striped (old owner was an ass) the screws were front passenger side of intake and the one right behind that, could this lead to the missing at idle i've been experienceing and the hanging idle??? Going to install helicoils tomorow and tighten it all down..hope this solves problem..I've tried every thing..and i mean everything else.

Well plugwires, IAC and TPS are all new and TPS was set properly, butterfly is seating good in THrottle body and Im getting 20HG at the tree with vac gauge. All lines check out fine...then i notice I can turn two screws on my intake with just my hand which I know is bad so I figure this would likely be a place where unmeetered air could enter, but id still like to know since like you said you have 2 bolts missing with no problems, would mine be affected more because its speed density and SD cars are more reliant on vacuume?