Cliff and others have warned about leaving an "extra" gasket below the inlet seat.
Please look at the image and interpret.  I think there may be a metal washer but if there is, it is stuck good, possibly by corrosion or got swaged by bead blasting.
Does this look like there's a washer or not?  I think the depth of the seating surface below the casting surface would be the best indicator but I have nothing to compare with.
If this looks "wrong", and there is indeed an extra gasket or washer in the body, how do I get it out?  Can I just whack it with a hammer and punch?  I'm obviously reluctant to do that if the sealing surface is good.
Thanks,
Mike