There are some examples in here:
http://hmvf.co.uk/forumvb/showthread.php?27143-Land-Rovers-that-fire-missiles!
This "conversion" is only taking it back to what it was originally. The NSN is not given but the Asset Code 1720 19 1777 makes no sense (to me) as in 1964 Asset Codes became 4 + 4 digits displacing the earlier 6 + 2 + 3 digits.
As it happens I have in front of me DCI (RAF) 1972 which lists all RAF MT with their Asset Codes. It confirms the description given above & indeed agrees with the record card. I see it gives the capital replacement cost as £1,555.
It lists a number of Trucks, Utility that includes Rover 1 to Rover 11. Interestingly it also lists Cars, Utility These include Rover 9/2, Rover 10 & Rover II.
I suspect there are various typos. As I think last type should read Rover 11 & in the Utility section it includes Series 1A & Series 11A.
So there were 7 types of Rover designated Car, Utility & 31 Trucks, Utility including 4 which are CL models.