patio sliding door rollers

Info to start: I live in Florida along the Gulf Coast, so you know I have a horrible time with corrosion. The rollers and springs on the bottom of my door are corroded. It took wd40 just to break the screws loose, but the metal piece sticking through will not come out.

I have a two part question.
A) Are the rollers 84-074 and 84-074N interchangeable?
B) The part that sticks out through the door near the two phillips head screws seems to be stuck. Do I just use a soft mallet and hammer it through the hole?

Thanks,