articulated lawn tractor build question

[Golden Rocket]

Ventrac & Steiner use one HST pump to drive both axles so getting the speed the same to both axles is a little easier than two totally separate transaxles.

I suspect getting all of the engine and transaxle controls linked from front to rear will be the biggest challenge.

I have been researching this same topic - just a point on the linking up of controls for frt/rear drives - the old school log skidders use a transfer case to direct drive thru driveshafts to front and rear differentials (I would guess they are of the same drive ratio of course). The driveshaft to the rear uses a constant velocity u-joint configuration to allow for proper flexing without the binding.