I'm trying to replace the coil packs on my 1990 Chevy Celebrity Eurosport Wagon with the 3.1L V6. The bottom bolts on each coil pack come out fairly easy but the top bolts all seem like a different size or all rusted out. The 5.5mm socket slips on one of them and the other two it won't grab onto at all. I have tried metric and SAE from a little bigger to a lot smaller and nothing will grip onto theses. I have also tried female torx and still no luck. On one I finally got sick of it and ground the head of the bolt off so that I could get the coil pack out of the way and have room to get the bolt out. The joke is on me, now the bolt is frozen in place and even vice grips won't break it lose. I have had it soaking in penetrating fluid for days but it won't free up. To make things worse the coil packs are mounted on the front of the engine so I am working blind and there is almost no room to get anything in the small space where the bolt head is. Any ideas?