The solutions (proposed by Guy) worked like a charm. I took my break bleeder tank and partially filled it with marvels mystery oil and added to it powdered graphite. After mixing it up good, I fitted my break bleeder tank with a 7/16" ID vinly hose. I then removed the ends of the throttle, mixture and prop cables on the engine side. Next I placed the 7/16" hose over the end of the cable and tightened it on using a small clamp. Then, I released the pressure from the tank in essence filling the inside of the cable assemblies with the lubricating mixture. This is known as pressure lubrication! If done properly, the mixture will start to ooze out of the throttle quadrants. This is when you stop applying the potion. Then, I exercised the throttle quadrants and the cables operate like new!

Thanks Guy for the help (and everyone else too). This is truly a wonderful solution. Naturally if they get worse again in a short period of time I'll replace them.

I recommend this for anyone whose quadrants are a little stiff!

Chris