340 mopar intake issue
So long as you are careful I think you're safe doing it without a cast boss there. Liquid pipe thread sealant will seal and be tight. But dont overtightent it. It only holds 18psi... so a little teflon thread sealant and you're good to go. I've done it for senders before and I wouldnt hesitate to do it again. You could also use the thicker section as the other posted did around the thermostat. Or have a chunk of aluminum tig welded over the water port area and bore into that. Then it's a little polishing to match.