First of all, it's a harmonic damper, not a balancer. It uses an outer ring of metal and a metal inner hub, separated by an elastic material to allow the outer ring to move slightly back and forth in relation to the inner hub. This slight movement cancels out the small harmonic vibrations created on each power stroke. When a cylinder fires, force is imparted to the rod journal of the crank and the metal has enough elasticity that it bends slightly, yielding to the pressure from the piston/rod. It will only bend so far though and when it meets enough resistance, it springs back the other way, past center until it again meets enough resistance to make it spring back the other way. If left unchecked, these harmonics will destroy the crankshaft in short order. The outer ring on the damper performs this service for the crank.

The longer the stroke, the further the crankpin can bend. That's why you see bigger dampers on longer stroke motors.

You can use the 283 damper on your 350 and take your chances. It may work well and it may not. I can certainly understand wanting to reduce the flywheel effect from the larger damper.

Perhaps some other members of the board can share some direct experience in this area.