So in prep for getting a shoe and ride plate, I see other (used) intakes for sale.  I have a Berkeley 12JC in my Hallett, and I see different part numbers or "12 degree" in descriptions of one for sale.  How do I determine what mine is and what interchanges?  Thinking of buying one already machined with a shoe/plate or getting a "spare" to send out instead of having my boat in 1000 pieces while I wait...