When the oil pump cable is removed, it allows the oil pump lever /spring to relax way around clockwise "over center" the wrong way. So, when re-installing, it is necessary to move the lever [which by this time is probably "up" or 12-1 o'clock, move it counter-clockwise past 9 then to about the 6 -oclock position, then screw the line end into the throttle cable plate. With the line attached properly, there is a mark on the lever that will indeed match a similar mark on the oil pump housing. In the attached pic, they are not quite aligned.
Since it is kinda difficult to move the lever c-clockwise back over center with one hand, while not allowing the cable end to slip out of place, while pulling on the cable with the other [not much room in there] ... On my several GTIs with 717 single carb engines, I cut about a 3/4 - 1" length of garden 1/8" irrigation drip line tube, slit it the length, and insert it over the oil cable just below the top end, so that it cannot relax /retract enough to allow the lever to go over center when the top end is unscrewd from the throttle plate. It's then much easier to re-attach.
Hope this helps!