Portable Generator Battery

What a calamity of errors. So as I'm taking the battery out of the generator, one of the nuts that you screw the battery cable bolts to comes out of the place in the battery post where it normally sits. It bounces on the ground and into a storm drain where it can't be retrieved. I try calling Champion one more time. Success! I get a nice guy who tries to help but in the end says, they can't sell be a nut but if I want to buy a new battery for $52, the nut and bolts come with it. I respectfully decline. Off to the Big Box store I go to get a new nut. Nope, can't get a new nut. HD doesn't have the right size out where I can try screwing the bolt I brought with me to it. Not a 1/4" nut but close. Must be Metric. Open the drawer where they keep the Metric nuts. They're individually packaged. Is it an M5 or an M6? Don't know for sure. Both look like they might work but can't rip one open to see if it threads on the bolt for sure because it wouldn't be right to do so and two employees are helping other customers literally 5 feet away from me anyway. So I buy 2-1/4" x 20 x 1/2" bolts and corresponding nuts from the imperial section of nuts and bolts. Back home, I try to insert the nut in the opening on the battery post. Nope, doesn't fit. Too wide. I grasp one of the nuts in a pair of vice grips and off to my Ridgid sander I go. I grind down two sides equally until it fits. Ok, grind the other one down. Ok. Problem solved. I put the battery on the battery tender. Oops, forgot to add fuel stabilizer to the generator. Ok, stabilizer added. Better start it up so the mixture gets through the lines and to the carb. Don't want that thing gumming up on me. Ok, battery is out of the generator so have to pull start it. Never done that before. Always used the electric start or remote with electric start. No problem. I pull and pull and pull some more. It won't start. I go take the battery off the tender and hook it up. At least I know the nuts and bolts work fine to attach the cables. I fire up the generator and let it run for 30 minutes. Ok, that should do it. When all said and done and I had the generator put away for the winter and the battery on a tender, it was only 2 hours after I started for a job that should take 5 minutes. Good thing it was 50 degrees today in Western NY or I would have been majorly P.O'd. I hate when these kinds of things happen!!!