Sterilize 8 Ball Quilted Crystal (#14400-81400) jam/jelly canning jars, lids and rings by boiling them for 15 minutes. Remove the jars from the water and allow them to air dry; leave the lids and rings in the hot water until you're ready to use them--the rings MUST be hot when used. If you can find them, you can also use 4 (1-1/2 pint) straight-sided jars. They must NOT have buldges in the sides of the jars or you won't be able to get the cakes out without digging them out. Look for the number of the jar I've given you--once you see what they look like, you'll know what to look for. Once the jars are cool enough to handle, grease them with shortening (DO NOT use butter, margarine, PAM or Baker's Secret). Fill jars 1/2 full; place onto a cookie sheet.
Preheat oven to 325-degrees (NO HIGHER!) Sift together the flour, salt, baking powder baking soda, cinnamon and cloves; set aside.
Beat eggs until foamy. Add sugar, oil, zucchini and vanilla. Mix well with beater. Add flour mixture to zucchini mixture. Add nuts.
For the pint jars, bake for about 35 minutes, moving the jars around in the oven so they'll bake evenly. Start checking the cakes at 25 minutes, and go from there. The bread needs to be done, but not over-done. For the 1-1/2 pint jars, bake for about 1 hour and 15 minutes; start checking them at 1 hour and go from there.
Using HEAVY DUTY MITTS (the jars ARE HOT!), remove the jars from the oven one-at-a-time. Place a lid, then a ring on top and screw down tightly. Place jars onto your counter top to cool completely. You'll know when they've sealed, you'll hear a "plinking" sound. In case you don't hear it, doublecheck the jars by pushing down in the middle of the lids once the jars have sealed--they shouldn't move at all.