sixpotter wrote:Now I need to find out whether its cheaper/easier to get these up and running or leave it and invest in some kind of diesel heater?
Easier and cheaper to repair the dash blower, but a bit time consuming.
(BTW This isn't an either/or option IMHO. You defo need a demister/heater fan, but you can also ask yourself "do i need a night heater?" and "do I need the rear blower?"
Demister motor is a whole dash out job, but easy enough if you're confident with the spanners. New blower motors available
HERE if needed. Check wiring/connections/fuses before you rip it all out

. Once out, it might be seized but "freeoffable". Give it a squirt of easing oil on the bushes and turn by hand. Spin it til it's nice freed off, connect it up and see if it runs smoothly and quietly. If so, put it all back - happy days!
sixpotter wrote:Are there any good specialists on here who can price one up to run off my existing tank and just how much work will be involved in sorting the original front and back motors out?
Anyone local who fancies taking this on as well

You could also go for a night heater if you feel you need one and don't mind spending a few bob.
There's one
HERE which is pricey but at least the guy can show you it working before you spend!