Remember do all this drilling and tapping for screws before you do the cotter pin part. Do a test run on the installed carrier before installing the cotter pins. It is easier to correct mistakes before the carrier is permanently attached to the window guide. This picture shows the screws inserted into the ears and some plastic covers on the screws. This is used so we don't have metal to metal contact between the screws and the window guide. I used insulation stripped off some heavy duty copper wire.

 

The final picture shows the completed assembly back in the car door. I was confident enough that this fix would last a long time that I put the door trim back on right after installing the fix and running the window up and down a few times. Some things I did to prevent further problems down the road were to apply oil or grease to the sliding parts and as suggested elsewhere to spray silicone lubricant in the window guides where the glass slides and wipe the top guide where the top of the window rests. This prevent the window from sticking at the top of its travel. Two tips that made re-installation easier for me: First, there are three screws that fasten the window guide to the door and it is difficult to push the top left hand screw into place. I cut 1/4" off the screw and it was a lot easier to get the guide back into place in the door. Second, the screws that fasten the metal carrier to the window glass can be tightened by using needle nosed pliers in the holes of the round nuts and fingers at the back where the screw heads are. No need to fiddle around with the 14mm wrench!
My car is a 93SC300 so I cant complain about how long this system lasted..17years is not bad!. The repair cost me about $2 for the screws and 6 hours of labor and I'm hoping for another 17 years!
One last thought although I didnt try it, if your nylon carrier is in good shape except for the steel block breaking out of it and you don't want to cut off the ears, it may be possible to drill all the way through the carrier and the window guide then insert cotter pins from the back side. Might work!

Again thanks to PerryinLA for the concept.

 

The cotter pin mod is genius! I did it last night and now it feels like I have a new car! Now to do the pass side tonite