Thank you Grant, I'll try this :). In the meantime, I had already connected the 4 steering servos not to pixhawk/ardurover to control but to my rc reciever and I've been just using pixhawk and ardurover for just for telemetry and navigation data collection. I configured two 3 position switches on my transmitter for steering selection for turn-in-place steering since I cant use the joystick for that. I only use the joystick for forward and backward throttle and driving.
Would your solution work for not just turn-in-place steering but arc u-turns as well?
Here is a video that I used of the manual switch approach to the steering. When I try your solution, I'll make a video as well and share.