Question about lights

[10PreRunner]

I plan on running my workbench against my garage wall. I'm wanting to put some LED lights on the ceiling, parallel to the work bench. My question is, how far out from the wall is ideal to mount the lights to prevent much shadowing? I know there are a bunch of variables but does anybody have a quick, good answer? Thanks for the help.

 

[Platonic Solid]

Ideally directly above where your hands are and full length of bench such that light from sides cancels out shadows.