[Ron Ramirez]

The first thing you need, assuming you are familiar with schematic diagrams and how to safely work on a vintage radio, is the schematic diagram/service information for your radio.

You should start here for that:
http://www.philcorepairbench.com/schematics.htm

Many sources of parts...the least read page on my website:
http://www.philcoradio.com/resource.htm

Finally, if you have any questions, please feel free to ask. If you are not familiar with the proper and safe ways of working on vintage radios, please get someone to help you. High voltages abound in old radios when the set is on; and you could be killed if you do not know what you are doing. (Hint: Never work on an old radio when it is plugged in!)