Uniden Pro510XL Not Transmitting

@Outlaw, great step-by-step advice. Also great background into how & what goes on in the final circuit for the rest of us who've been following this thread since the beginning.
@Rfrazee, any chance you skipped that step about the nylon shoulder washer that attaches the final's transistor mounting tab to the chassis hole? That has to insulate the tab (collector of the transistor, which is at around 13 volts) from the chassis (which is at ground).

Also, is there any chance that the final that the OP got *isn't* a pin-for-pin swap with the original? I know it's unlikely, especially in a TO-220 with the big heatsink tab mounting hole, but if the terminal legs don't have the same pinout, that might be the origin of the short. @RFRazee, is it possible to show us a scan or pic of the diagram that came with the new final that shows the legs and the identification of what's marked as E, C, and B?

Just a thought, besides the most obvious of either another part that was left on the chassis that was shorted to ground after the blown final was pulled, or that the new final was replaced. I didn't think of that back when it would have been timely, like during the time he was waiting for the new part to arrive, i.e., ohm out the positive terminal to ground and make sure there wasn't another short to look for.