You need a high pressure line which is probably what you got from DM. That will go from the PS pump to the rack.
For the return you need either a stock line (which it doesn't sound like you have,) or a 17mmx1.5mm (or something like that, don't assume I'm right there,) adapter to -6AN, which DM also sells. You can then attach an -6AN to 3/8" push lock hose end, run that hose back up to the reservoir. I believe the reservoir fitting is the right size for the 3/8" hose, but again, I'm not 100% certain. Then I think the supply hose from reservoir back to the pump is something big like 7/8".
Key thing there is you have to come up with something that will screw into that oddball 17mm threaded hole in the rack to get a line back to your PS reservoir. If you want to run a cooler (you probably do,) that's the line you'd run it on.