I've been reading this form for a while during my search for a van and now I've found one I thought I should (re)introduce it:

It's a 1987 1.9l Autohomes Komet conversion with a recon engine from 2004 and new gearbox and clutch from 2006. I say reintroduce because I think it's been owned by a Syncronaut before so some of you might recognize it?
I've been fixing 3-point seatbelts in the back for the kids and getting to grips with everthing that may, or may not need to be fixed up. It all looks pretty good so far, some seam rust and a few more serious patches, well...small holes actually, in one wheel arch and in both front steps. I'm going to take it to a specialist garage for a more through check than I'm capable of doing next week so hopefully there's nothing serious that I've missed.
I'm planning to use the van a lot this year because I'm working on a major photographic project that will cover inaccessible places all over the UK. This van will be my transport, accommodation and office for all my location work.
And now here's a really dumb question so please forgive my ignorance: What's the procedure for engaging the diff locks? I've tried the toggles on the diff-lock panel but where I would've expected to see lights there was nothing doing. I've tried this in neural and in gear (1st and G) but still nothing. Does the transmission need to be moving to engage the lock? Is there an idiot's guide out there?
Thanks in advance.
Dom