Kent -
Super busy these days so sorry about the delay.
In my opinion, the Little Buddy (we have the Portable Buddy) should heat your TT just fine. However, if I were you I'd go pick one up at Lowe's or HD so that if it doesn't quite do the job you can return it easily. It will definitely work fine if you move it around to where the 2 of you are - dinette, bed, batbroom, etc.... I just don't know if it will heat the entire 1985 evenly.
The reason we have the Portable Buddy is because of our previous larger popup trailer surrounded by canvas. Our 1575 heats up quickly even with our single tent-end (that does have a solar blanket on top & Reflectix in the windows in cold weather) so the Little Buddy would work for us.
Another reason I like the Portable Buddy is for power outtages at home. It will heat our master bedroom or kitchen or family room nicely while we are awake. We've had to do that 4 or 5 times including once a few weeks ago.
One more thing - I do feel that the Portable Buddy is more stable than the Little Buddy for safety reasons.
And of course - whichever you buy, PLEASE DON'T SLEEP OR LEAVE WITH IT ON! 