While removing stock manifolds from the Tahoe, I noticed the stock manifold was missing back bolt on passanger side near the # 8 spark plug. After removing manifold completely and and checking head I see there appears to be a broken bolt in hole. Don't know if this came from factory like this or broke somewhere along the way. Don't know how hard it will be to try to get easyout in there and try to work it out. Does anyone have any advice?