Specifically these are J5 gangs, based Antelope units, some of the early versions even still had the sprockets on the left end of the cylinders. Make sure that there is no wheel wobble which, if not attended to, will lead to the drive pinions destroying themselves and the ring gears cast into the insides of the wheels. Both the pinions and the wheels are getting hard to find so it may be worth inspecting them all sooner rather than later.

After posting my reply re your gangs something was bothering me and then the penny eventually dropped (age thing!) – they appear to hitched up the wrong way round!. It’s more usual to have the single unit leading. That sent me burrowing through the manuals but all I could find is an operators manual for the very early units where their Antelope ancestry is very apparent. Looks as though your hitch may have originally been for a five set rather than a three. Anyway it may be of interest

https://www.dropbox.com/s/s4io0a0f5au44c2/Ransomes%20Junior%20Gangs0001.pdf

On the wobbly wheel issue I am wondering whether as they have a cast wheel running on a steel (hardened?) pin that the wear is more likely to be in the wheels. If the pins mic’ up more or less standard would an option be to put oilite bushes into the wheels. If you go the new pin route you would probably have to true up the bores in the wheels anyway.
Just a thought!
In the early 80s when the councils were changing from cylinder mowers to rotaries we could buy as many Antelopes as we wanted and in quiet times used to make up hitches etc and sell them as gang sets. Fortunately there was a guy in Worthing who had a thing about Sloper engines and would take them all to re-engine 17″ Suffolks etc. As you might guess we didn’t bid against each other!