1.  Can I drill a new hole in the Bellcrank (where the pushrod attaches) by 1/8" closer to the center without upsetting the geometry significantly?  only two brackets to change or
2.  I could fill/drill new holes in the attachment bracket and move the whole bellcrank assembly closer to the trailing edge by 1/8" which would required 8 holes filled and redrilled or
3.  other suggestions?

The easy and all together best solution would be to simply produce 4 new brackets with the mounting holes slightly offset. The kit should include the right piece of angle stock for the job. This way the geometry will not be changed, your nut plates will still be in the correct position and you don´t have to fill any holes.

Regards
Tim Jorgensen
360FB  /  60%