Heres something else to think about.
Polaris doesnt have a differential in the front, its a spool. Thats one of the reasons EBS wont engage the front wheels, it would be almost uncontrollable if you had one side slip and not the other,coming down a loose hill.
If you did figure out a way to make it full time 4wd, youd be misserable. It wouldnt steer very well(no differential action)and parts would probably wear very fast.
Ive heard the ratio in front is different than the ratio in the rear, thats so the front stays engaged in 4wd . That would be tough on parts, in a high traction situation.