If you don't have a Webasto heater for engine coolant then you need the additional tube into the tank unit, this runs forwards to the metering pump then across the floor to the Eberspacher.
If you already have the coolant heater (under floor left side) then there should be a 'T' piece to provide the take-off for the Eberspacher metering pump.
If you haven't got pick-up pipe in the tank unit then the various Eberspacher suppliers will supply you with a kit to fit it in your existing tank unit. Bowers at Stoke on Trent are one who should be able to supply.
I've fitted a number of Eberspachers in T5s &T6s and am also in Shropshire so if I can help please feel free to PM me.