I am doing a PI swap on a 1997 GT. The old crossover has 2 temp sensors and the new one has 0 sensors. The new manifold is off a 2001 GT. I need to drill and tap two holes in the new crossover. All I can find online is that they are 3/8-18 but the ones on my old crossover are closer to 5/8. what is the thread size?