Any links to any threads available detailing the exact differences between the run of the mill J and L suffix R380's to suit TDI/TD5's

Stashed under the bench is a J suffix gearbox that was stripped down due to a c clip failing taking a chip off the 5th gear pinion, the box drove well with no issues apart from the tooth presenting itself when dropping the oil. I have TD5 Defender now with L suffix R380 and would like to free up some space by stripping off the good spare parts and scrapping the rest.

Whilst I appreciate there were several key improvements in terms of uprating bearings between J and L suffix I was wondering if the gears, syncro hubs etc are the same. If its not worth hanging onto may just get rid of it it to free up some space.

Thanks