[Lynn Eades]

If you google "thread data charts", Go to the one that says just "thread data charts". There is a list that says British fine (BSF) in there under the .750"Dia. (3/4") it says there are 12 tpi (teeth per inch) That is the thread on your spring rods.
Like I say, your axles are a special thread. Measure the dia of the thread, and count the threads or check with a gauge. Then hunt around the various thread charts, until you find what it is. It is a very fine thread for the dia. (it may be something like a "cycle" thread.
As far as basics go the steel in your carrier is in metric sizes, but none of the threads are.
All the other threads are BSF(British) except for the ones in the Ford componentary(engine gear box diff)which are almost all UNF(American)

So all the countersunk screws(flat or round head) in the hull etc are BSF.,the majority of which are 5/16. BSF.,3/8 BSF.,and the screws in the tow eyes, are 7/16 BSF.
All the wheel bearings are metric (6000 series) except the fan extention which are imperial sized. I cannot remember what the one is, at the bottom of the steering column(I think imperial) If I recall correctly the flat Tecalamite grease nipples are also BSF.
As far as you axles go, I would take all the damaged axles, and nuts with me, when visiting your friend, because I think you will be hard pressed to find a set of dies, and a die nut or a tap to suit. They will need to be repaired on a lathe, even better if your friend has a suitable thread chaser.
I Hope that helps, and best of luck with your project.
Maybe you can let us know how you've got on with the various issues you have to work through.