Balancing a Scat cast crank

I built a 416 a few years ago.
Scat 9000 crank, Scat I beams, ProTrue pistons.
It balanced internally without heavy metal.

I supplied the same part number crank and rods to another customer this spring, along with Icon pistons.
Needed heavy metal for internal balance.

For the next one I used a Molnar steel crank and h beam rods, same # Icon pistons.
Had to take a bunch of weight out to balance it.