Hey so ended up coming into a 2001 rx sat for like 7-8 years so I got it running actually fired up pretty quick but I just went through and cleaned the carbs rebuilt them and everything changed the fuel lines oil filter and all that trying to button everything up and the exhaust bolts pipe to manifold the first bolt in sequence I'm suppose to tighten won't tighten it just spins has anyone had a similar issue are the threads trashed in the manifold if so any ideas or suggestions of how to fix