Here's the vent tube I made from an oil dipstick tube. It's not fully pressed in as there isn't much room to swing a hammer and I wasn't going to lower the axle just for that.
My car was missing the vent tube, probably from day one. I bent up a replacement using a dipstick tube. I made up a tool to drive it into the housing. It looks totally original. I can take pictures if anyone's interested.
Just trying to save you some potential grief. I couldn't use studs on the passenger side when I put 340 manifolds on my small block. I usually use blue loctite on exhaust studs and it even seals heli-coiled threads.
The pump is a GM saginaw power steering pump. Parts from GM vehicles are interchangeable so you have lots of potential donors. Follow this link for some good info. Just keep in mind that they're talking about trucks. In my experience the original steering gear on our cars is very forgiving of...
After a lot of searching I found this write up. It points in the right direction.
https://www.pirate4x4.com/threads/modifiying-saginaw-power-steering-pump-revive.2712489/
Hi, I'm having a lot of frustration with getting my pressure and flow setup for my Borgeson steering box. I wonder if you have come up with a satisfactory combination. I'm testing a 7 1/4" dia. crank pulley and I still don't have adequate assist at idle.