Fitting Showchrome heated grips

[bikerdog]

Hi I have a 2003 GL1800 that came with no heated grips.

I have a pair of Showchrome heated comfort grips. The clutch side seems straight forward but the throttle side needs to be removed by removing the throttle cables as the heated grips come complete with the piece that takes the throttle cables. I cant seem to get enough play to remove them. Are there any tips to make this easier?