The GS 500 has a setup like you want. I dont think it would work or be visually apealing, it would need to be a really long shifter and the way the case is set up with shifter shaft in a recessed area it would be almost impossible to get it to work properly without a series of complex bends.
I took another look at it. It could be done very easily...and simply. The reason I have abandoned it is that there is no support on the shifter shaft. We are talking about 3 inches to the first supporting bearing. I do not want to add any bending moment to the shifter. Right now it accepts and takes a torsional load. If I went to a direct shifter it would add a bending moment.