No 2H / stuck in 4WD


Sorry for this but I have been going round the interweb in circles today. I do realise that this is basically a known issue, but cannot fathom it out. History:

a) my local garage fitted a new clutch some months ago - no problem.

b) then the gearbox lost synchro on second gear, so got the same outfit to fit a second-hand replacement. But somewhere along the line the replacement box got knocked into fifth (the cog on the back) before the transfer box was fitted, so when it came down off the lift car wouldn't move. By a process of elimination I helped them realise the issue......

c) so they had to remove the transfer box, then refit it, problem solved.

d) ten miles later (after they closed) the 4WD light came on whilst driving. Research indicates a vacuum pipe issue?

I have been underneath this morning and also removed the gaiters cover. I see a jumble of wires and tubes, VSVs not fixed, the whole lot tied up with cable ties. I do see an F shaped connector, with a 30mm tube on the top of the F, not connected to anything - is this the vent to atmosphere tube?

On top by the gear lever mount, is a T shaped hose spigot. Is one side supposed to be piped to the spigot on top of the t-box? Is the other side supposed to be connected to anything? Couldn't see this on the web pictures.

Assistance appreciated.