CB750 Exhaust Studs

Picked up a '71 I am starting to get back on the road. I wanted to install studs for the exhaust flanges rather than using the bolts that were in the exhaust. It looks like the bolts are 8mm. Anyone know what the thread pitch or length would need to be? Or is there a kit somewhere I can just order a set? Do they need to be any special grade or material since they get hot?

If they're M8 I'm pretty sure 1.25 is the standard pitch. I'd check by going in to a hardware store with the bolt and and trying to thread it in to a 1.25 pitch and 1.00 pitch, see which is easy to do. Stock bolt is M8x22mm. So, I'd say go 25mm plus and get a nut. As far as grade, I'd assume whatever the stock bolts are would be fine.