Gordon does your ignition switch get warm or hot to the touch ? The ignition switch in my 68 fried several years ago. On mine I had the key ON without the motor running trouble shooting a fuel pump problem. I looked up and smoke was pouring out which resulted in mad scramble to unhook the battery. It melted some of the wiring going thru the tach. Once I got the switch out it seemed pretty light duty quality. I still have it and it. It is a Lucas switch and has 34503H stamped on the body. I replaced it with Lucas p/n 34680. That one seems much better quality and heavier duty. The 34680 I got came with new keys but there is a hole in the body to insert a punch and depress a pin and remove the key tumbler and I was able to swap my original key tumbler into the new switch. No more troubles since.
David Barnes
68 E-Type FHC