I'd start by cloning out the stiletto peeking out from behind the gas pump on the right side. They didn't have them in the 50's.
Somebody forgot to tell Betti Page that, as well as the artists that were drawing them on most pinups of the era.
I think she needs a classic pinup era hair style from the 40's or 50's to really sell the "pinup genre'.
I would also have featured her next to the pump, showing plenty of leg, up to some short shorts or skirt, pump in hand and a look on her face like she can't figure it out and needs help - while looking at the viewer. Those are classic elements of pinup.