transmission gears

Hi everybody, I'm new here and I could really use some advice. I've got a 2000 1.8L protege and my f25m-r is at deaths door. Fine by me. I've been wanting to change over to a g-series anyways. A few months ago I grabbed a g-series tranny from a 1997 escort spi because of the 3.85 final drive...

I drove it the other day and then it randomly just revved up wile driving and won't go from there... Sounds like its a transmission problem.. I heard that it could be a cracked LSD. I'm not sure. Should I get a new tranny or buy the LSD and try to install it... Anyone know anything about it ...