If I get the Pump assembly, I am assuming it will be in Pieces. Am I going to get good Schematics with it?
I found what I think I need-Part#893906a02.

I am just afraid I may not be able to put it together without good schematics.
Does it include the body/housing and everything?

Other question is, I was told by the instant answers person that my power trim unit, if I get the whole thing is Part #12-898447t01. I cannot find this part on the website. My Serial # is OGO39215 Yellow fille Plug. What is the cross reference to this part number, or is there one?

893906A02 Pump Assy is the right pump. It will have to be assembled to manifold and there wont be any instructions comes with part, you need service manual for instructions.
The Complete Power trim pump is part number 898447T01, here is link to price
898447T01 PUMP ASSEMBLE, Power Trim

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