I went to do a simple bulb swap and ended up with a big head ache.after swapping the bulbs I went to install the housing and it wouldn't make contact with the plug. Turns out the plug won't stay in place when pushing the housing in.i had to get my hand behind the plug via the wheel well to make a secure connection. How do I get the plug to stay in place? Also what are the high beam part numbers and other bulb numbers in the housing?

 

It's possible the stationary plug the unit plugs into may have a broken stem causing it to tilt backwards when you're installing the headlamp unit. Or, it could be you don't have the unit in its "grooves" so the plugs are not in alignment. As for the bulbs, in my 1999 C2 the bulbs are H7's for high, low, and fog lights. Hope this helps.