Got them installed today and did a short test ride, weird swerving for bumps instead of away from them.
10 minute install using a scissor jack to take the weight positioned on the engine bar right under the rear brake reservoir. Removed both because the 13 inched would not go on one at a time. This is also a method to get the front tire off the ground, basically uses the jack and kick stand to make a center stand.
Spring rate is not too different from the R3R stock rate. Sag was correct with 1 full turn of preload for all 190lb of me. Seat height is about the same as stock, I suspect the extra 1/2 inch of length is compensated for because I can actually get correct sag now.
Damping is massively improved mid turn when hitting a bump, tracks true and sucks up the bump. The front really does feel like pure garbage now :/
Part number 440-4238C, I haven't been able to find what bike they originally intended for, it is either R 3 or generic large metric cruiser. Either way the eyelets have the correct bushing already installed.