Brian,
To get back to your #2 original question, I have attached a couple of other photos posted by TUTS 59 of a 1942 GMC engine compartment he spotted/posted in the
Stovebolt Spotters Alert forum that better show what the PCV valve and line to the valve cover look like all together.
Also, just a suggestion that your questions about the "brakes" are better asked and discussed in a forum related to that topic (not really on topic for the Engine Shop forum). You haven't told us what your truck is, but based on the described brake equipment, guessing it's probably a GMC "Big Bolt". The best forum to post further questions on your truck is most likely in the
Big Bolts forum.
Hope this info and the bit of redirection for further questions helps you get the answers you need for your truck.
