wow... it looks like you got the worst of all worlds!
if the photos on the ebay auction are correct, the lights themselves have the BMW style plugs... I will get you part #'s for those in a minute.
The 'universal harness' isn't going to get you too far. Your sealed beams have a 'hella/H4' style 2/3 prong plug, and the depot lights have the OEM style connector in the caps and city light. So the harness isn't going to help you. There isn't much point to 'converting' to 9006/9005 plugs at this point.
So, I would try the following:
I think you might want to try to keep your existing wiring plugs, so get 4 male 3 prong 'hella/H4' style plugs with push-in spades. You will then need:
12 BMW# 61-13-0-007-445 plug wires
(2x lowbeam, high, citylight for each side)
2x BMW #61-13-1-378-417 white highbeam plugs
2x BMW #61-13-1-378-419 yellow lowbeam plugs
2x BMW # ?? blue city light plugs.
Wire the above into the male hella style plugs (on the lowbeam side you will need to test for which of the two hot wires is hot for the low beams), and then clip the bmw wires into their respective plastic plugs. You will probably need to tap into the sidemarker wires for the city lights... You should then be good to go.
I will try to find the part # for the lowbeam and city light plugs.