Almost time for the machinist!

just read through this thread
the grove in the bushing is for oiling the gear- good idea
YMWV on the rocker geometry
but if heads are stock unmilled now and valves are same length and cam base circle is stock small mill should not require new pushrods-
hyd lifter will take up the difference and NOT change the geometry
just measure the depth on each end chamber then mill flat to get them all four ends the same
the middles are what they are
If the heads have been cleaned up on a belt sander by a quickie rebuilder previously they will take a lot of milling to get them back square do check with a deck mike- they are cheap and an essential toolbox item
as others have said check the block then bore as little as possible- if no rust MOPAR (and AMC) blocks are tougher than brands X
how much ridge?
how do you clean the oil gallies without taking all the plugs out?
detail your oil system first
drill the main feeds to 9/32
I have found broken drill bits and partially drilled holes ( from too many sharpening/ shorting bits at the factory)
clean up any roughness and round your corners
square corners kill flow (turbulance)
bottom tap alll your bolt holes
you did your porting so you can do this
Why not the KB quench dome pistons
they were designed especially for your heads and they really work