Hi that is part of the early extra called "pre-set linkage" it was fitted as a draft control ?! For early majors before the super came in with it all built in - its a simple but effective tool and hard to come by - there should be another part attached to the top cover - a bracket with 2? Metal bars that g from that part to the hydraulic lever - I'm sure someone has a picture - but google it
1963 fordson new performance super major. And An array or fordson parts and pieces !