Disco 2 Transfer box help

my 2001 td5 does not have CDL fitted to the transfer box as standard-(yes I have checked)
I would like to fit a transfer box that has the cdl fitted,I have seen lots of boxes for sale,some saying they are off an auto some off manual.
My question is-would I be able to fit one from an auto vehicle or does it have to be manual only?
Is there any differences?
Any help or advice is always appreciated.

There is only the ratio to consider.
Auto LT230 would be of a V8 . Don't buy a NAS one they have a big aluminium wart sitting on them with a superfluous doooda in there.
The problem is to find something to close the hole, so you have to make it ... Has happened to me and I have learned since.
PS my Disco 2 has at last the 300tdi linkage