Unfortunately the AKTA Prime is very simple and there is not much room for customising. If what you want to achieve is to run the Gel filtration from the bottom to the top of the column, the most simple solution is indeed mounting the column upside down. Now if for some reason you can't do that, you can rewire the system by attaching the buffer lane at the bottom of your column and the top to the UV, it does require additional tubing though. In general with the AKTA is not possible to reverse the flow.