I also made custom lower mount, have not yet managed to get bike rolling, but at least without spring the swingarm movement seems progressive as it should be. I had few test units first done as 3d print to ensure correct position and progression. Found inspiration from here but no drawings so with a help of friend made my own.
1100n frame, k1 1000 swingarm, k5 1000 shock and a mix of k1-k5 linkage parts.
Most likely needs custom dog bones to get balance right. Might even need repositioning of top mount, plan is to make all fit without cutting anything on frame.
few pics attached
