Spark plug reach

Hey guys,
I’m trying to find some spark plugs that fit a 5/8 wrench because the 13/16 are way to hard to get in and out with my Schumacher headers on my 440.
My problem is that all of the 5/8 plugs have a .750 reach.
I have 452 heads that are shaved down, and flat top pistons at 0 deck height.
It seems to me like a .750 reach would be too long for these heads. Does anyone know of a 5/8 plug that has the .375 reach?
Here’s a picture from when my heads were at the machine shop. You can see the thin wall around the spark plug hole. If a .750 plug were to be installed, it would stick way out into the cylinder. I don’t think it would hit anything, but it seems wrong.
97FA4DFA-CDB1-4B39-984E-B1977204098B.jpeg