I need your help with my vacuum tap (and my manifold studs, too).

The factory manifold studs are double ended studs, 5/16-18 x 1/2, 5/16-24 x 3/4, and 1 3/4 inch long. The 5/16-18 end threads into the head. Broken studs can be a pain to replace, so 'if it ain't broke'......
jus sayin....