Check that C40E spacer and see if the bottom of the spacer has a small portion that curves out (and not run straight like the other 3 sides) at the nipple where the pcv hose would connect. If it does it will not seal against the manifold. I found this out the hard way. I ended up drilling an aluminum spacer like Canadian Hot Rodder.

Dan      Kingman Az.      86409

Initially I used a 2" aluminum spacer and tapped a 3/8" hole into the back, to thread in a PCV valve. I now use a 2" phenolic space and run the PCV valve from the valley pan into the back of my carb (570 Holley Avenger). Only reason I changed from the aluminum one to the phenolic, was I gained 12 FT/Lbs of torque by doing so!  

I love the smell of burning rubber in the morning!

Putting my rebuilt 292 back together with a Autolite 4100 carb on a ECZ-9425-B manifold. This is a later 292 without the road draft tube and a PCV port in the valley cover. I need a carb spacer with the PCV tube connect and have seen the FoMoCo C4OE-9A589 spacers available. Typically these are listed as fitting the 289 and 302 running a 4100. It "looks" like it would work and I wondered if any of you have used it on a similar setup?