When removing your master cylinder you must pull that piece that holds the clutch pedal and brake pedal in place. I found an old bicycle spoke is perfect for the job. You can use a new bicycle spoke if you please LOL. Insert the end that would normally be in the hub and you don't even have to go all the way in, it will pull it right out with ease. Just thought I would pass this on. Everyone else has been helpful so I thought I could be helpful too.

All tips are greatly appreciated!

If you don't already own it, buy the Chevrolet 49-53 Passenger Car Shop Manual. It has detailed instructions for this and all other repairs with detailed photos and diagrams. It's the best forty bucks you'll ever spend.

Avail at Filling Station,Chevs of the Forties, Natl. Chevy etc..

There is a youtube video that shows the pedal shaft lock pin, titled "1949 Chevrolet Master Cylinder"

http://www.youtube.com/watch?v=U98d0uUhfDg

My shop manual says to use a piece of stiff wire to remove the keeper pin and the You Tube Video shows the man having a great deal of dificulty with his wire with a bent end. My suggestion was the bicycle spoke . Absolutely no trouble pulling it out. You don't need to go to the bottom and have it catch the other end like you would need to do with a hook, but just about half way in and pull the pin out.

I do have to say that is one of the most comical videos I have seen that is trying to give instructions for pullin' the locking key!

I bet it happens this way lot's of times. Once you get the lock key out please tap the hole in the end to 10-32 all the way through and then the next time it is pulled just screw a long 10-32 machine screw in the threads and pull! I had to do this on a master cylinder that had never been greased and was really stuck. also, throw the pipe plug in the end of the master cylinder away and screw in a Zerk fitting and about once every 3 or 4 years put just small squirt of chassis grease in there, don't go overboard on the grease and get it under the master cylinder's rubber front boot. This will keep the shafts greased and prevent excessive wear on the shaft bushings.