A neighbor wants me to do some work on his dad's old Hiawatha. He wants to replace the skip tooth sprocket, chain and rear hub to 1/2" pitch. And paint it back to the original blue and white. I'll be replacing the handlebars, stem and pedals and the seat. The stem is stuck, flipped the bike over to look for the serial number and half the bolt fell on the ground, someone must have tried loosening it and snapped it. I've got most of the parts except pedals and a seat. And he would like to know what year it was built. From what I've been able to find online it's a Shelby built bike. Serial number X30520. Any info on the year would be appreciated. Thanks.