Help with drawing a part

[f350ca]

I think your over analyzing this Mayhem. A set of proper engineering drawings would allow a machinist to make a part that he's never seen and has no idea where it goes, what it does or what it fits against. Ken has an advantage here. The undimensioned drawing you have with an end view and the boss at the back should pretty muck nail it down. Sketch it up like Terry said some draftsmen could do and send it through to the machine shop.
That said one feature that concerns me, the rear mounting face appears in the photo to be at an angle to the boss and bore, hopefully thats just an illusion from the photo. Does the slot at 315 degrees do anything?