59A/B intake Pcv valve conversion

[SkylarknMerc]

Hey guys, I'm looking for info on a pcv valve conversion for a 59A/B intake.
I tried to do a search but came up empty.

I have a 255 8CM Mercury, and currently running the PCV valve where the old down draft was before.
Earlier this year I came across a deal I couldn't pass up on, a pair of Offenhauser #400 heads and a 4 barrel Holley 390 cfm and Offenhauser intake to match.

Doing some research I found out both heads and intake will fit on my 8CM, the heads I have to plug a hole on the block (?) And the intake will fit too, but won't have the downdraft tube hole , and the oil fill tube in the intake manifold that came on the 8CM motor.
Since I'll be running an electric fuel pump, the original mechanical fuel pump mount will be blocked off. I was thinking of installing the PCV valve on the blank plate by drilling a hole in it for the valve.
Has anyone done that or will this not work out?

Thank you in advance for taking the time.