This is something that I can't understand.
Penske entered PC16-Chevy's in 1987, then all of a sudden witdraws them and replaces them for Marches.
Should those cars not have been entered to begin with? To my knowledge, none of the Marches was actually entered.
Or could you simply change the car you entered for an entirely different car as long as you had an entry to begin with?
#25 started out as a Penske PC16-Chevy, it eventually became a March 86C-DFX.
Somehow, Penske must have entered such a car to begin with, under whatever entry number and then renumber it.
Or they must have taken over an entry for a 86C-DFX.
How legal/allowable was all of what happened?