Allan, actually this skimmer has the old style becketts. Shaun, most people actually do plumb this skimmer externally but I don't trust the older style becketts since they're not sealed. The skimmer is actually at louismutdies's house. I will post some pics and dimensions.
Just to give you an idea, here is my old MR-2 plumbed external to my sump. I upgraded to the new style injectors on this one.