Car tire on front
This thread didn't get a lot of response so I visited an area Trike shop this morning and asked the same questions.
The response makes sense so I will answer one of my own questions.
You can replace the motorcycle front tire with an automobile tire and you can gain additional mileage on the tire. Somewhere from 7-9,000 miles up to 12,000-14,000 with the auto tire.
But you lose the trike's ability to turn and react quickly because the contact patch on the car tire is so much bigger. The motorcycle tire is rounded and has a smaller contact patch making it easy to steer. In fact, changing to a car tire would have the effect of defeating the purpose of an easy-steer rake kit on a trike.
So, I guess when it comes time to change the tire I will stay with one designed for a motorcycle.