I have been having intermittent antenna problems and would like to replace the current radio/tape SC-810. I have been looking at the new Alpine receivers. I would like to know how difficult it would be to replace just the radio with a new one, e.g. Alpine. Are there any special tools? Also, where could I get info on how to remove the current radio? Also, does anyone have any recommendations the best radio, fit etc.., for a 93-850-GLT?