I think John's been advertising his choice for a while..
Ok, maybe that is a stretch but if you connect the following dots:
Tasca was given a Force chassis to race with.
I believe Tasca is the only other racer NOT on Team Force using John's Mustang molds.
John and Tasca Ford go way back.
Tasca is pegged for the 4th car.
Now to add another element to the whole deal...
I get the impression that John has been developing him for something much greater that Alcohol Funny Car. Not that an Alky flopper isn't respectable, it most certainly is, but it's not Nitro!
I personally think that Tasca may have been lined up for Team Force for quite some time now, not as a 5th car - but to step into John's car when he decides to retire. "Next Generation": all young drivers running for Team Force. If you think about it, it seems to make sense (at least to me). So putting Bob III into the 4th car makes alot of sense.
Now what are the chances of Team Force in a few years being Force, Hight, Tasca and Todd? That I guess we'll just have to wait and find out.