Exhaust bolts leaking coolant

have a 65 413, stock heads, just rebuilt. replaced the manifolds and studs with headers and bolts, now the front bolts are leaking coolant. Apply sealant? Run studs w/ headers?

apply silicone sealant to the treads,theyARE wet.

I leave all the studs that I can in place.But when I ran bolts I used silver antisieze.Never had any leak and they always came out.Rocky

running OE shouldered studs is the best if they will let your header flange fit & can trim the outer fine threaded portion so there's only enough threads left for the nut to fit flush & any more threads is a waste & hampers fitment & can also get a high grade nut that is thinner so you can shorten the studs even more

I left studs in the water jackets and sealed them with blue permatex for waterpumps when I put the studs in about 2-3yrs ago. Just swapped over to headers, left studs in place. Still no leaks.