this reminds me of what we raced 1991... superoldschool...
I raced a Yankee 1/8 buggy in the end 80s and early 90s. They came up with the funniest rear constructions you can imagine. But on the very rough tracks in that times it worked quite well (if it did not break...). And it was fully adjustable.
The image is taken from
Yankee-rc.com