I spent the big bucks and went with one of those fancy high torque gear reduction starters.. My problem is as follows..
I hooked the cute purple wire on to my solonoid, and when I turn the key to start I am getting a +12V (On my Fluke 87V MM), I have the three power wires on the big lug for the starter motor itself.. What I can't figure out is why the solonoid won't engage..
What did I mess up?!?!?!

 

.601 K ohm across the solonoid leads.. I tried a different key, I tried jumping one terminal right to ground, still nothing.. I think I have a bad starter solonoid...

 

Just had the Solenoid wire in the wrong spot.. Moved it to the other terminal and it worked..

 

That was gonna be my guess as I was reading your post. I installed a high torque gear reduction about a month ago and say there was no markings on the solenoid. One terminal had a shunt to the lug that goes to the electric motor so I figured it was the other. A check for continuity between the terminals and lugs confirmed which one to use.