SB Chevy Lifter Noise

I have a 350 that has excessive lifter noise that will not go away.
It almost sounds like the lifters just do not get enough oil or
something.

Have tried adjusting 1/4 & 1/2 & 3/4 & 1 full turn after clacking
stops. none of those adjustment steps worked.
Have installed new rocker arms and new pushrods. no help.
Added powerpunch. no help
Run 10-40 oil
The motor is basically fresh and clean (new rings/bearings)
350 nothing special for 66 Impala SS Ragtop.
flat top pistons
camel hump heads (redone by professional)
Edelbrock Performer intake
Edelbrock carb.
Reground cam 224 duration 467 lift
could it be bad regrind or bad lifters...

Any ideas would be appreciated, if nothing else, going to order a new
cam/lifters to see if that helps. Only drove the car once last summer
cause the noise annoys me so much.. (does sit in garage).

Thanks!