68 FURY Heater/ Blower woes……………

Now my 68 Fury ragtop is on the road, I'm sorting through the less important problems and this time of year in Blighty a heater/demister is suddenly the most important thing in the world.
I've read the thread from FuryIIIski about his 72 Fury and have a slightly similar set of issues on my 68 though the control unit looks a bit different and the issues are slightly different too.

The buttons on my push button control unit are very sticky to move but do go in and out. I don't get why the blower doesn't work -even if the vacuum unit is totalled surely the blower would still work.............???

Before I rip the entire dash out in the quest for a working heater system, is there any checking or places to look at??

It used to have a/c but this is long gone. How much dismantling is required to get to the problem parts??
Am I looking to virtually take the interior out -as I had to with my Mustang just to replace a heater core..?????

Any thoughts would be appreciated as I'd very much like to keep this job simple and sweet.
Author: raindance654