Several members have gone with the Timbren suspension on new builds, as well as retrofits.
I designed my 'rough road' tear build around the Timbren (ASR1THDS01) and have all of the suspension components on hand, but have not yet been able to get started (but maybe soon - I hear that I can buy steel again!).
I do believe your trailer to be the prior year version of the Starcraft/Starlite that I own. If so, I believe there would only be two guaranteed complications for converting to Timbren:
1. The frame extension in front of the wheels, that supports the door sill, and its counterpart on the other side of the frame. This may need to be modified somehow, to allow the Timbren suspension to mount on the frame. That, or notch the Timbren bracket.
2. The frame should probably be reinforced in the mount area, and would definitely need a doubler on the inside, to get enough width for proper mounting of the new suspension.
Another major consideration would be whether or not the Timbren suspension is going to align the wheel with the skinny little wheel wells that these trailers have.
If you want to ponder the conversion and take some measurements, the Timbren spec sheet is here:
Timbren Axle-Less ASR400-7000 Dims Specs Imperial Rev032918Most of us are using the 2,000 lb, 2,000 lb HD, 3,500 lb, 3,500 lb HD, or 1-Tonne (down-rated 3,500 HD due to longer swing arm and more travel). Beyond that, the differences are in the different spindles, to get the desired ride height for a specific application.
A quick look at my trailer and the Timbren spec sheet (dimension 'g', front of bracket to axle centerline) leads me to the preliminary conclusion that frame modification (beyond a doubler) would be required for everything in the above categories except:
2k (standard) ASR2000S01/ASR2000S02
2kHD w/ 4" lift (w/ and w/o off road tire spindles) -- ASR2KHDS04, ASR2KHDS03
3.5k (standard) w/ 4" lift -- ASR3500S06