That's an excellent question. I have a list that I created on my home computer, but it isn't published anywhere. The best place to start is with the brochure folder in our files section. You can browse floorplans there:
Sunline Coach Owner's Club - Sunline Owner's Files - Sunline Brochures
Assuming the trailer you're looking at has original paint, you can narrow down the year some:
<1982: Creamy white exterior
1983-1989: Tan exterior
1990-1991: Light gray exterior
1992-2007: Bright white exterior
Model wise, it's important to remember that these model designations don't mean much. It's like saying you own a Ford F-series. But in that, there's the F-150, 250, 350, etc, so you are likely to say you have an F-150, 250, etc.
Same thing applies here. Here's a model summary written from memory, that'll help break down the product lines:
Originally a small motorhome produced in the early '80s, but from the '90s to the end, it was the flagship model available in lots of floorplans.
The "Lite" designation of Solaris is simply assigned based on length. The T-2475 and below were considered Solaris Lite for a few years in the early 2000s. As far as I know, there's no difference between a Lite floorplan from one year and the non-Lite counterpart from the next.
In the '80s, it just meant small trailers under 18'. From 1992-1994, it represented all trailers under 23', with Solaris being the 23'+. From 1996-99, Saturn trailers were an economy line with the same construction, but less features.
Trailers in the 18-24' range, from 1986-1989.
Luxury trailers built from 1986-1991. Basically an option package for all Solaris floorplans in that time. Also applies to the Sportster truck campers, so you could buy a Seville truck camper too.
A small 17' single axle trailer, fully fiberglass sided, only produced in 2007. Very European in design.
A toy hauler travel trailer built in two floorplans from 2005-07. All were fiberglass sided and unlike most toy haulers, the garage was sealed off with a vapor barrier wall.
Economy lines of trailers built from 1988-1991. They used a different numbering system, but many floorplans overlapped with the respective Saturn/Satellite/Solaris floorplans.
A small, 10 1/2' teardrop style trailer built in the late '70s/early 80s, and pretty rare. Not suitable for substituting cottage life, lol.
From 2000-2002, these were revolutionary aluminum framed, taper body, fiberglass sided trailers available in some unique and some copied floorplans. These have been found to be pretty leak prone, in case you're looking at one. The name was reintroduced in 2006-07 for a production built wheelchair capable trailer.
Sunline's first trailers with slide outs were marketed using the Slide Room name in 1998 and 1999. They later became "Solaris Slide Room" or Solaris SR. The SR part was dropped as a special designation by 2005 and they were just all called Solaris. The 1998-99 Slide Rooms were largely based on the Saturn trailers at the time, so they do lack some features from a Solaris.
An economy line of trailers, similar to the Saturn of the late '90s, built in 2004-05. They had unique floorplans to the Sole line.
A continuation of the Sole line, but in an effort to improve sales, they made them appear more like a Solaris. Some of the unique floorplans carried over along with some new ones.
Lightweight gooseneck fifth wheels built in the early '80s. As far as I can tell, the SunRider V name wasn't advertised on the trailer anywhere.
A small, Datsun chassis-based delivery van built much like a Solaris motorhome in 1980.
Travel trailers built around 1974-75.
Truck campers 7'-9.5'. Some overlap in floorplans with Sportster.
Truck campers 8.5' to 12'. The overlapping floorplans with Runabout generally had a few more options than the Runabout version, but for anything smaller, Runabout is the only choice.
One final note to mention, there is a lot of overlap of model numbers between years, but in some rare cases, some numbers were recycled later on. One that I can think of is the T-1950, the floorplan in the mid '80s is very different from the 1994-2007 floorplan.