That's 70's technology? Wheres the punch tape? Ha!
On most controls you can set H parameters in the controller (H1, H2 H3 etc) and call those out in your program for your different cutter lengths. That way, so long as you don't move them in the tool holder they'll always be at zero when returned to the spindle.
One way to do this is to zero your spindle nose off something, then measure your different cutter lengths off that same thing. The difference is your H number. Then you can zero your spindle off your work piece and any program that calls out an H value will compensate for that tool length. You see, H is a positive number that equals the distance from the cutter end to the spindle nose. There are other approaches to this, but I think this is a easiest to understand.
Then, if you have another work piece you can zero your Z with your spindle nose, or if you lack Z travel, you can activate a tool length compensation, load that tool and zero Z with it, and now all your others cutters are zeroed too (assuming you call out their H number appropriately in your program)
MasterCAM is good stuff. I use Pro/NC. Do you surface mill your bevels or are you just profiling your blanks?
