I have a mate with a VW frame-buggy with a 40 Hp motor and swingaxle gearbox. He'd like to put a kombi-gearbox in it with reduction boxes. Does he need to change the whole gearbox or can he just change over the axles and hubs?

I have heard of just changing the axel tubes and fitting the boxes...
The trouble is,, you have to take the Crown wheel out and out it in backwards...
With the Boxes.. they only have 2 cogs in them...It reverses the direction of the rear drive.
So if you dont have the crown wheel turned, you will have 4 reverse gears and 1 forward....
(Learned the hard way)
It can be done, it works well with the 33X12X15 Mud tyres on the back...
I think the you have to modify the spring plates too... but i cant rember... too many

:beer AGO!

could be the perfect oportunity to go mid engined

Col its probally quicker to change the whole gearbox, as you will have to turn it on its side to remove the circlips from the drive gears, etc etc

Yes the crown wheel is in the other way around as well.

You will probally need the rear trailing arm spring plates as well... they attach different to the reduction boxes as to a Beetle.

its that word association thing again, as soon as my mate Dave mentions crown ........
the crown wheel is in the other........
I immediately walk to the fridge
:beer
cheers.

CROWN now that i think of it Colin bring some with yar OK

just check the width of the axles to see if they aren't too wide\short!and yep, i think i would be changing over the whole box with spring plates too. its a good ratio[in the later ones anyway] for a buggy i am told!
cheers josh