"Unfortunately the switch on my car isn't located in the same way as the one on the film.......' Rusty1, At this point, you're over thinking it. No worries. We're all 'new' and uncertain at some point. Yes, the switch is located differently, but, I can assure you, everything else is identical. The basic switch is the same. How you remove the knob is the same. How you remove the switch is the same. How you unclip the harness is the same. First thing I would do is pull the knob. That can be done without disassembling the dash. With the knob out of the way, do you see a nut similar to what is shown in the video? If yes, you're golden. If not, the bezel has to come off. A little involved, but, its just a matter of removing screws. Good luck.
Update Hi all, it's been a while since I have written about the Plymouth but I thought I'd update to say that I have finally sorted the dash lights. I had a mechanic fit a replacement switch only to find that the dash lights still didn't work! Finally managed to get them working when I made up a wire lead and tried adding a new earth. Bingo! Lights on. I also added a new bulb holder for the light on the very left of the panel - turns out that this light only comes on when doors are open and then there is a short delay after doors are shut. Thanks again to all who made helpful suggestions and gave advice. Rusty1