I made mine from 1/2” aluminum tubing and a prebent 1/2” fuel line I found on the net. The valve is a V100 which has 3/8” treads on one end and goes towards the intake. Mine Is in a 90* elbow between the carbs. At idle on my engine the vacuum on the engine internals is 1.5” of vacuum which is correct for our era of engine. V100’s are common replacements for 60’s engines PCV valves and about $6.00. Remember to add a rubber or leather seal under the dip stick flange stop. I also bought a Stant oil fill breather cap with a hose fitting built in and ran a hose to the inside of the air cleaner so only cleaned air is sucked into the engine. 

If you are going to use the valley pan fitting shown make sure there is some type of baffle under it to deflect splashing oil. I used the stock 63-64 truck valley pan with an attached deflector and fitting. I believe the Thunderbirds had these along with 62-up Fords and Mercury’s. The side front breather also needs a plate. I found a T-bird one on line for mine.