Washing between bed cap and rear window.

[snarl]

Does anybody have a better way than pulling the cap back every time I wash the truck?

 

[Kira]

Rain-X all glazing involved so power washing can be as effective as can be.

 

[R_W_M]

There are a few ideas over on the Ford Rnger Forum:

http://www.fordrangerforum.com/cleaning-and-detailing/75306-cleaning-topper-cab.html

 

[MasterSolenoid]

How much space between the two ?
That may dictate a method most appropriate.
You only have to get 1/2 way across the vehicle and clean from both sides.

On the Ranger Forum previously posted; someone suggested a Swiffer Handle (for cleaning floors).
That would require 2" of space.

 

[Garak]

Yes, what MasterSolenoid stated. My old F-150 has a fair bit of room, so it's not much of a deal to get a rag in there as needed. I've noticed some of the trucks these days have very little room. Detailing forums may have some idea, too, and some of the detailing sites have interesting, twistable microfiber pad scrubbers, for want of a better term.