Clemco that was last winters projects. there was a few of us built some.
I built 3 before getting one that was decently controlable
in lght winds it would keep up with a blowie. we got to the stage where speed became an issue, then spring happened and we all went sailing instead.
yours looks like a good one. hav a look in the landyacht register , there are some photos of some that we built

I sailed one of the original french ones "a fair few years" ago, heaps of fun, but very painful!
The Trans Sahara had a class for these, and some of them achieved astonishing speeds, well bundled up I suspect. From memory over 80 km/hr. Stuff that!

mostcommon injury was bruising to the ankles from that rear axle, hence my final version had 1 rear wheel. the trick wih them was not to try and go slow or in a light wind. you needed to have a bit of sail area and wind and just go for it.
Oh and learn to roll!

how did you attach the new axle?