I'm considering pressurizing the rocker shafts on  my '55 292. I know there are at least a couple of methods, pinching off the shaft drain tubes appearing to be the easiest. My concern is about possibly starving some other part of the engine for oil. It looks like the output of the passenger side shaft goes to the timing chain. I don't know where the oil from the driver side tube goes, distributor/oil pump drive gear maybe...? I'm pretty sure a few guys here have done this so I'd like to know what method you used and the results before I pull the trigger. TIA for any advice.

Thats all I use on my engines, that stuff works good.  My 56 would normally get 3 weeks before the humidity here would result in separation of ethanol and fuel in the tank.  I started using the Stabil 360 and I can go a good 7 or 8 months without separation but the gas does get weak.

I also toss a bottle of Redline lead subsitute as well as my engine is original from '56 and I do plan on a complete rebuild with harden seats but my grandfather drove this car hard though foot always on the floor and it still running but lead gas was as far as i could tell was still avaliable in the early 1980s at some stations so maybe that is what saved this engine.

1956 Ford Fairlane Town Sedan - 292 Y8 - Ford-O-Matic - 155,000 mi

I think it's wise to go with hardened exhaust valve seats while the engine is being rebuilt. I know that "G" heads can crack between seats, but I have no direct knowledge of that occurring while installing hardened seats. I suppose it has much to do with the condition of the heads and who is doing the work. Having to baby it while driving can be stressful and takes the fun out of the experience. If in doubt, ask the man who knows. His name is Ted.