Hi abricker,
Welcome to Sunline Owners Club and congrats on your new to you Sunline!
No worries on the questions, ask away. There are no dump questions here, we try to help as we can.
Your model is not that common but that does not mean a member may not pop in that has a similar one. I though I recall a newer one showing up on the forum a year or so ago.
You may be able to yourself back into the approx dimensions if we provide you with some features to look for.
For your year camper, the tanks where held onto the bottom of the camper with small metal plates every 8 to maybe 10 inches to hold it to the floor joists. They look like this,
And here is a basic tank setup. This is mine after I added a tank sprayer to it.
Look to see if any of those metal tabs are left hanging under the camper. They may have screwed them up tight. If they took the plates off, look for a series of 2 holes in a row on a floor joist in a pattern which will outline the perimeter of the tank.
If you are fortunate to have the plates left, then measure from screws on plate to plate to create the width of the tank flange. And ideally the all 4 ends of plates are left and you can back into the entire tank flange size. Then you have a lot to start with finding a new tank. Just have to find a tank to fit those flange dimensions or close to it and be about 35 gallons.
Following this link
Sunline Coach Owner's Club - Sunline Owner's Files - 2000 Sunline Solaris & SR Travel Trailers
You can download the year 2000 brochure which lists your camper. The brochure says your black tank was 35 gallons and the grey tanks was 35 gallons.
Is your gray tank still in place or did they take that tank down too?
Hope this helps and good luck
John
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Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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