That's a big rod balancer , remember that 440 4bbl in 70 also had the big rods so it used the same balancer/dampner setup. Also noting the 2 drilled holes, to my eye the crank was balanced with that attached to it so I would not just remove it . What did it have on the back , flywheel or flexplate?

I had a speedpro forged piston/big rod combo internally balanced , it took very little standard weight slugs welded into existing holes to do it , why Chrysler thought they had to external balance these engines is beyond me.