To OP, did you ever solve this problem?

something else I would check since I know im guilty of it...

I believe its generally the same across all platforms/engines, but there are 4 wires.

Battery cable
Alternator wire
Black wire (ground I presume)
and a Yellow/Black

Try putting the yellow/black on the lower terminal if you havn't already... mine starter would spin all day but just didn't seem to pop out the gear to crank it. Thinking I had a toasted starter, i bought a rebuilt one and threw it in... same symptom. Reversed yellow/black from top and put it on bottom, worked like a charm.