It's an interesting thought from catman to aim for a prebend of the frontbeam of some mils under load.

But I really don't know if that will help with the right adjustment.
Because there is the matter of real heavy dynamic loads during the sailing. You can imagine that by meeting waves, jumping and/or sudden windblows, the front beam (via the mast) has to cope with short dynamic overloads.

When the frontbeam is bended down the horizon shortly by overload, the load on the bolts on the sides will reverse from pushing to pulling sideways. Also very shortly, so giving a real shockload.

I think the bending beam itself can survive this swings easily. But if this happens often it may explain bolt-damage (other than supposed corrosion).

This may mean that you have to give so much prebend that this never happens, or atleast as less as possible.