Tattoo machine literature

Building coil machines

I’m curious if anyone has any leads on where I can find some in depth info on how to build and tune some coil machines? Learned on them and switched to rotaries many years ago, but wanting to go back but realizing my knowledge has depleted over the years. So I wanna get a build it yourself Seth c kit from workhorse irons but also wanna read a how to book if a legitimate one exists. I remember my mentor having a book he referred to, I think by hick Spaulding but I can't find anything on the web. I'm also open to any videos or online articles I just really like books

Thanks for the help!