Okay well basically, what drives the pump is nothing but an offset wheel attached to the timing chain sprocket called an eccentric. I doubt they actually went through the trouble of opening up the timing cover to remove it. If the did you can always buy the eccentric at most auto part stores.
I must agree with you that this is a rock solid part that doesn't need to be complicated. If it works good then whats the problem.
here is what they look like
Mustang Parts from Mustangs Plus*::*Fuel System*::*Fuel Pump Hardware*::*260/289/302/351W Ford Racing Fuel Pump Eccentric, 3/8" Bolt