I have just grabbed a screen shot of each of the Manuals we host here for reference.
So the 15x7 rim on the early GQ is a Pos5
Screen shot 2014-12-09 at 6.35.27 PM.png
The 16x8 rim on the GU is a Pos10
Screen shot 2014-12-09 at 6.36.40 PM.png
and the 17x8 on the later GUIV and onwards is a Pos10
Screen shot 2014-12-09 at 6.38.02 PM.png
The offset for the Splitties are also listed