Here is what I used for measurements on my homemade shooting bench...benchplans.jpg
This size seems to be perfect and works well for me and is good for both lefty's and righty's. The legs can be made of whatever you want. The height of the bench is 30" floor to top of the bench. Of course you make it so that it's comfortable to you.

Hope I'm not too late before you made your cuts. In any case it can give you an idea and others in the future.

Fab