Aussie rider returning - seeking assitance Cam chain

[drifter-paul]

Hi all. I was registered with this forum a few years ago, but have forgotten my old login details. I remembered an article on Cam Chain Tensioner Extenders - should have printed it and used it earlier. Now it is too late.    Having refound the article by Tim Acree I checked my 1500 99' Drifter and i have 3/8" 10mm extension , Tim says 5/16" is OUT OF TRAVEL and he's right. It was full of oil.

My questions are  - 1 - is it easy to remove the 'spark plug tunnels'  and replace  ? Do use just use a 1 1/4" /32 mm hex slug inserted after              removing the spark plug?
- 2 -  any tricks for replacing the Cam Chain/checking if it needs replacing?

I'll locate my Clymer Vulcan "classic" 1996 - 1998 manual (closest I could get to a Drifter manual in 1999) and go thru that. However, any expertise/shortcuts from this Forum will be much appreciated . 
Many Thanks, drifter-paul (Australia)