Defender OM606 & auto conversion help

Hi guys I wonder if you might have any suggestions for an auto box to go along with an OM606 in a '93 Defender 90. I am in the process of sourcing an engine and have a ZF 4HP 22 out and ready to go and a ZF 4HP 24 in a driving P38 I know the 24 is a stronger box but is it the best option? Has anyone done an OM606 conversion with an auto most of them I have seen are manuals. The main reason I would do the conversion is to get the auto box.
On another note which of the Land Rover shows is the largest as I am hoping to do a trip next year from Ireland with a few friends and we would be staying for a few days so a small show you would get around in a morning wouldn't really be an option, I used to go to the billing show about 15 years ago and always enjoyed it and I was hoping for something similar or are any of the shows that big anymore?
Thanks for your help in advance.

There's a guy in plymouth made his own adaptor plates, but I think MD Engineering do them too ... and Ashcroft might be a good source of info.

The 24 is the stronger box, but in a '38 will be the 24E - electronic control, which Ashcroft can deal with using a compushift 'puter box thingy .....

I'm interested how you get on, as the OM606 is a fine injun, specially so if converted to solely mechanical injection - I'm sure it'd make a fine conversion for 90/ 100 / RRC / D1