I don't think you can follow the path originally trodden (competing on asmone 68K/hw with your fellow local coders, exchanging snippets of hw reg info and source) however there's a terrific short series of videos on youtube you might consider:

https://www.youtube.com/@WeijuWu

Wei-ju Wu lays out how to code directly on the hardware in an accessible manner and, importantly, from C, instead of 68K, with lots of examples. Then, if (or rather: when) you have to, you can always step down a level into 68K assembly to get better performance.