Biggest intake seat insert a Dove head will accept, trying to save head from dropped valve.

Guy didnt check valve clearance and after all the valves smacking pistons he finally broke of one and valve got pushed into bowl and seat . Measuring looks like a 2.30 should take out pretty much all of damage. Throat was big like 2.00 so need big and deep of insert as safely possible. I read exhaust can hit water at 7/32, but cant find info on intake seat, appreciate any help...,ED