Leimbach has this 2x 6ch device that'll allow you do that Scott. But then you can't "walk" up a steep hill using the arm with the tracks. Using a radio with proportional sliders between the sticks is ideal.
First ever lifesize excav I ran was a 40mt Hitachi, which was at the same time I was building my first model excav, so I set my tx sticks the same way.
lft stk up/dwn = boom
across= swing
rht stk up/dwn = stick
across = bucket
Caterpillar is some other goofy way like S/S B/B or vice versa.