Carbed vs your guys' TBI I know, but my truck has a nice easy to floor gas pedal, whereas my dads is hard to depress.
Both are Q-jets, both are cable throttle, so something is obviously binding. Not a very complex setup, I'd check the pedal for binding, (maybe hair or insulation where it pivots?) the cable, and finally the throttle body.
I believe the pedal comes out really easily, (its disconnected from the cable easily at least) I know the cable can be disconnected and checked really easy, and so can the TB at the same time.
I HATE hard to depress gas pedals, and when dealing with a manual trans, its even worse.