While helping teach @JOEL340 how to use Onshape, we designed a 3 motor flipped gearbox with a dual output shaft. The gearbox is designed interchangeably, just needing to swap the motors, the output the two gears for the last stage and the spacers to completely witch from falcon to neos or vice versa.
The NEO gearbox is 9.29:1 with an estimated speed of 13.72 feet per second. The gearboxes use 13 teeth to 42 teeth, then a 16 to 46 on the second stage.
The Falcon Gearbox is 11:08 with an estimated speed of 12.93 feet per second. The gearboxes use 13 teeth to 42 teeth, then a 14 to 48 on the second stage.
Onshape Link to the drivebase and gearboxes.