Both the Parts List and the Shop Manual for Tigers show the PCV valve as a right angle assembly, part numbers: C3TZ-6A666-A for valve and 378754 for adapter, these are no longer available. You might be able to find one of these assemblies in a junkyard or you could make one. The adapter could be made from a brass elbow or machined from square metal stock.
I found a similar threaded PCV valve Part No. AC Type CV-643C, it also had a Ford Part No. C4ZE-6A666-A. Alternate PCV valves are AMPCO PCV-484, which is very similar, and AMPCO PCV-58, which is taller.