motors won't crank

Hey guys! I think I finally got my left engine working. The NGK spark plugs were all over the place with their gaps (0.75mm, 2x 0.65mm, and 0.35mm) and super dirty, so I cleaned them and tapped to 0.22" (0.55mm) per manual. I also filled half the tank with 87 (was 91) and bypassed the fuel...

It all began in Oct 2012 when Sears melted my brain by installing the new battery leads backwards. Their insurance co. stepped up to the plate and $2400 later I now have the conversion kit installed that you guys were kind enough to tell me about, and I have found a good mechanic who seems to...