300i6 intake manifold
 

Ive been trying to put my 76 F150 with a 300 back together and i dont know what screws into the threaded holes on the intake manifold? I was thinking the brake booster line but the hose isn't long enough is there a pipe or something that goes there? A picture of one would be good. I got the truck disassemble and I'm slowly putting it back together.