[Milsurplus] GP with ARB?

[Jack Antonio]

It seems logical that at some point the ARB receiver was used with a
GP series transmitter.

However, is there any written or photographic evidence for it? So far
I've only found references to the GP series used the the RU family.

I did find a reference in a pilots manual for one of the blimps, that
an RU-17 was used with a GR-12 transmitter("intra-squad") radio, which
leads to the question of was there a GR series transmitter? Or could 
this have been a typo, the letters F and R are next to each other on a 
keyboard.

Mostly idle curiousity, but with a goal in mind.

Thanks

Jack Antonio
WA7DIA