It's been a while since I have been in a 43 series . I can't remember if it was a double U joint and is it possible to get the joints out of time like a drive shaft .
depending on what you are working on . I use jack stands on all 4 axels not the hubs . If you want to place jack stands under the frame I put a 2x6 between the frame and the jack stands .
The VH4D in your 610 will always stop in 1 of 4 places it's just how it is . You need a new ring gear on the flywheel . You need to pull the engine to change it . foton suggested pulling the starter but i don't think he's ever done it on a 610 its a heck of a job with absolutely no room to work...
Just never run a 610 out of fuel . you did it once you won't do it again . You will learn to keep it full and use only non oxy 91 to save you a lot of headaches
If you don't have a timing light get one . you can't own a point distributor engine without timing it . Wisconsin engines are great but they need to be maintained . I have been rebuilding Wisconsins for a few years and I have seen many with broken top ring lands because the timing was to far...
Join the Melroe owners of America group . at the top of the tabs go to the files section . you can download everthing for free . I just did a 700 service manual took iit to a print shop . printed it and put it in a 3 ring binder for 50 bucks .
is your variable speed in low ? Also Check your engine timing . If you don't have a timing light get one . I can't stress enough how important the proper timing is on these engines . I rebuild them and see broken top ring lands from to far advanced timing .