Some info on Ross in the later years:
Ross' top three models would have gone something like Super Gran Tour, Gran Tour, and Gran Tour II. The Super Gran Tour would have been a Shimano 600 equipped with Araya alloy rims, the Gran Tour had Dia-Compe Brakes and Shimano Titlist/Altus derailleurs with steel rims and high flange alloy hubs, and the Gran Tour II would have been probably Dia-Compe brakes (either side or center pull) with low end Shimano derialleurs and steel rims and low flange steel hubs. The next models down were the Eurotour, Eurosport, and Compact, which often used a Shimano Front Freewheel system, one piece cranks, and steel mostly steel components.
The Redcay and Kellogg built bikes came about in the early to mid 80's and were nearly all Campagnolo, Dura-Ace or second and third generation Shimano 600 equipped. (Components could be specified when ordering these bikes).
By 1985 the Super Gran Tour was replaced by the Signature series, which consisted of 4 models, the 290S with Shimano "Z" derailleurs, the 292S with Shimano 105, the 294S with Ishiwatta 024 tubing and Campy Triomphe, and the Triad 508 with Columbus SL tubing and Shimano 600 (I believe 6400 series).
An Allentown, PA built bike should also have a date code stamped on the rear dropout opposite the serial number and in '77, I believe they used a round red and silver aluminum "Ross" glue on headbadge. All of the custom built frames I've seen have has the newer "R" logo decal badge. Pre-Allentown bikes were Asian imports and of lower quality, they wore a headbadge which read "Ross" "import division".
Ross bikes, other than the Redcay and Kellogg models, don't seem to have much collectable value, like Ollo Ollo said, they are good for the sum of their components. The Redcay and Kellogg bikes were built to order bikes, and were few and far between, most serious riders looking for a custom built high end bike probably weren't going to be looking at Ross as an option. Somewhere in the early to mid 80's Ross shifted production to military ammo boxes and all of the bikes were then imported from Asia. Not long after, Ross went bankrupt and the name was sold to Rand Bicycles which is and was a department store bike builder. 1985 is the latest record I have of Ross in Allentown, PA. I am not sure if the bikes in the '85 catalog were still being manufactured there or in Asia, there warehouse was huge and probably could have survived several years on old inventory from the Allentown plant.
The last I heard the Allentown plant was still sitting abandoned, since the bankrupcy and sale, and the property was contaminated and awaiting cleanup. This was in the late 90's. Maybe someone in the Allentown, PA area can update us on that matter.