Any baby-boomers remember the mimeographed, send-away-for, papers called something like the Lankton Bureau Rocket Project from the late 1960s? They were step-by-step instructions of how to scratch build and mix solid fuel, etc. I do believe that I still may have the papers in my archives and promise to dig for them. Another was a company that sold casings, fuses, chemicals, etc. to build fireworks. I think they were called "Caseco"? Different times back then! I did some Googling with not much success... Thanks!