I would suggest removing the cable from the control on the handlebar, may give you more slack in the upper cable .
I have had issues with '82 and later R65's, my LS's .
On my '81 R65, you need to push the upper cable down in the splitter plug, move it to the side and it should come free .
If this doesn't work and you have an '82 or later bike, you may need to use a very thin file and ' open ' up the slot on the splitter plug, for the cable you want to remove, the swaged cable end needs to be pushed up from the bottom side of the splitter body to do this then pulled out the side of the ' plug ' that the cables rest in .
You only have to open up the very top of the slot to get the cable out .
Hope this made sense to you !!!!

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