Thanks for the link, and for your email explanation, Martin! I've just finished the repair, and all went well. I removed the clutch cover and clutch basket and did the repair as described in the link you posted. (Funny, those instructions don't mention the bit about the blood and missing skin when you try to rewind the ratchet with your fingers!)
I thought a lot about the discussions of easier repair methods, and concluded that it is unlikely that this repair could be done without removing the clutch basket. If the end of the spring did not pop out of the ratchet gear, it would be theoretically possible to rewind the spring tension, but practically almost impossible. It would be impossible because the kickstart lever cannot be rotated far enough to rewind the spring. The lever interferes with the clutch cover, and so has a limited range of motion. Too limited to re-tension the spring. With the clutch cover and clutch basket removed, you can rotate the kickstart lever 360 degrees, and most of that 360 degrees is necessary to wind the spring adequately. Just my observation. Some people may get lucky.
As long as I had the clutch apart, I also filed off the rough edges of the clutch basket "fingers" to improve the smoothness of the clutch. I also welded an extension on my clutch actuating lever, to make the clutch lever lighter in my hand, without removing springs. Now it's after midnight, and I'm tempted to go back out and install the new tires that arrived today. I have a long holiday weekend, and I want to ride the bike!