Whats the best solution for the Oil filler tube hole in the front of older engines 283/327. I'm installing a Edelbrock rpm maniford, shall I Plug it with a Freeze plug or just cover it with the intake? If I dont cover it will it lead to blowby?

I also pulle the heads off just too see if I had any P to V problems using the 461 w 202/160. Well i did find a tiny, tiny little shiny area which look like it could have glazed each other. I was thinking about putting smaller shim gasket (.015)to get a tighter quench and bring up the compression a little but seeing the little shiny area has detoured me from that. I measured the piston to deck using a machinist tool and I have 1/32 pistons in the hole. Is this common or could it be possible that this block has been deck. I had the machine work done 13 years ago but did not
fire the engine till this year and wipe a #6 cam lobe. I will probably get the Z28 springs, retainers, guides and seal for the heads to insure that they are in top shape. Wil;l them spring work for a Summit Cam part#1102.
* Advertised duration: 262 intake/272 exhaust
* Duration at .050 in. cam lift: 204 intake/214 exhaust
* Gross valve lift: .420 in. intake/.442 in. exhaust
* Lobe separation: 112 degrees
* RPM range: 1,500 to 4,000

On my old 283 when I put a performer on I just covered it with the intake and put different valvecovers on that had a hole for adding oil.