I tried to do a search, but had no luck. I have a long brush
with soft bristles, so I can climb in the bed, and scrub the
top, no problem.

I was wondering, how do you wax/polish/remove sap/etc.?

Even with a ladder, the area towards the windshield is tough
to reach.

 

I usually stand in side the door and hang on to the oh **** bars inside. It is kinda hard to do so i only wax the top every other time. as for the back, i stand on the edge of the bed that is against the rear window and i can reach pretty far there too.