Headlight Dimmer Switch

Help!!

Any idea how to replace a headlight dimmer switch in my 78?     It’s located on the steering column but not sure how to get to it???

 

 I think I need to purchase either the service manual or assembly manual. I’m looking for step by step instructions and not sure which manual to purchase, any suggestions help be appreciated.

 

Thanks

The Dimmer is on the side of the column and might need adjustment, I nbeleive if the mount screws are loose it can move some but here is the location

Bob.....I buy a Haynes manual for every car I buy. They are very helpful and are step by step instructions. I think everyone that has a Corvette should also have the AIM for it. I use mine all the time., and I also have and old original Chevrolet shop manual that I bought on ebay. I don't use it as much as the others.

Thanks for the info and advice.  Hopefully this isn't over my head.  I'll give it a try on Saturday!