If you look around in the files area, there are a number of Sunline Owners Manuals that have been scanned and posted there. Since the manuals are NOT year specific, the info in a 2004 manual is pretty much identical to what was in a '94 manual. It is mostly generic stuff about winterizing, care and use of the trailer.
As Gene said, the rest of the manual was all the appliance, etc. manuals placed in a three ring binder.
If you need a specific appliance manual, look through the files area. A lot of them are there. Dometic's website has a bunch, too dometicusa.com
atwoodmobile.com has lots of their manuals online for download, too.
My '99 T-2453 has one page that was model specific. It is a detailed floor plan with pretty accurate locations of all the features of the trailer. I have been encouraging folks who have that sheet for their trailers to scan and post them in the files area.
The files area has most of what you want.
'12 F250 4x4 Super Duty PowerStroke 6.7 diesel
2011 to present: '11 Cougar 326MKS
1999 to 2011: '99 Sunline T-2453
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