Hi to you all,I'm new to the forum.Gearbox is hard to get into second so I've got a guy who will rebuild it but needs a good workshop manual.any suggestions much appreciated .1999,19td camper thanks

Hi and welcome to the forum.

With gear selection issues on cable shift boxes it's always worth greasing the gearbox pivot as a first resort (if this hasn't previously been done)

If you're confident enough to try it yourself there are several threads on the forum detailing the procedure eg.

https://www.fiatforum.com/ducato/296026-ducato-2006-clutch-gearbox-issues.html

Most gearbox selection troubles are related to a dry or worn linkage and not to the gearbox internals. Spray it all with plenty of duck oil including getting some down any cables.