Finally...
Got the gumption to remove the wood frame that held the 24" RCA TV in the cab overhead. Only the 8 1-1/2" wood screws that attached the frame held the TV in place. To keep it from sliding forward, at the rear base of the set there was a 12x1x1" wood strip nailed to the wood platform that the TV just sat upon (the pressed-wood sheet which supports the overhead cabinets also sit).
Test drive showed much quieter w/ no heavy set to amplify overhead vibrations. Still some wood to wood squeaks, but radically quieted overhead now.
Will now consider how to make some sort of storage space for stuff like blankets...something light.
Must decide what way to go for TV/DVD replacement...Anyway, will soon want a notebook PC for trip routing software (Streets and Trips and maybe the TL directory on CD, perhaps). Will miss the large TV screen, however.
Any thoughts...