Thanks for the link to the speaker pix.
Look what I found: http://www.photobucket.com/54gmc100
Looks to be the original speaker and grille (I found it stored outside in an old file cabinet tat I almost threw in the dumpster while cleaning up Dad,s property a couple of months ago) The other pix are of the truck new in 1954 and the project that it has become !!!

1955 GMC 1st First Series Deluxe Cab
In the Stovebolt Gallery
More pix on Photobucket

Tax the rich, feed the poor
Till there are no rich no more
Just black and white, rich or poor
Them and us, stop the war.