Many thanks Mark and Steve. I have a confession to make. My foot well lights in my Mk 4 where there all along! It's just that the interior of my car is entirely BLACK (unlike y Mk 3 whch is blue/grey) and at first glance I thought the only light in the foot wells came from the interior roof light. It was only when I switched off the roof light as well as the garage lights that I could see the foot well lights functioning correctly. Ah, well, I'll be 73 tomorrow. That might explain it!
Pepe