meathead

So I bought a used rack(not the smartest idea, I know). I mounted it but it was leaking from the cylinder lines, not the supply or return lines. I unmounted and tighten the lines and still there was a leak. I'm going to try and re-flare the lines but I was wondering if there was a way to test the rack before I mount it.
Connecting the supply and return lines is a pain so I would like to save myself the effort the loss power steering fluid if I can test it without mounting it.