It's all just bloody difficult sometimes. I don't know what behaviour is just typical kid behaviour or what behaviour is down to his additional needs. And even that there are so many opinions on how to actually deal with said behaviour.
It really really is. There seems to be no official guide book but those are the resources I've found to be the most helpful. You do have to screen out 90% of what people say because most assumptions people have about behaviour are not going to apply in your case.
I'm home now so I can try to sort out the recs a bit more.
If you find yourself often dealing with the question "Why is he doing this?" or up against behaviour you aren't sure if he can control or not, or if your attempts to change behaviour seem to make things worse - look at the dysregulation stuff. Because this helps you differentiate between conscious behavior that can be managed or strategies taught, vs stress behaviour, which is hard to address directly (you need to address the indirect ie the stress behind the reaction, and teach self regulation skills and practice co-regulation).
That's Brain-Body Parenting and Self-Reg. Maybe The OT Butterfly too.
If you're fairly good at noticing when the behaviour is something controlled vs a stress response and you're looking to reduce/manage the stress situations, look at The Explosive Child, Too Fast Too Tight, OT Butterfly.
If you're fairly good at differentiating these and you're looking for something to help build specific skills or solve specific problems,, look at the points system or the explosive child or the ADHD specific books or anything at all to do with executive functioning.
If you are wondering what kind of impairments ADHD and ASD causes at the root level rather than just at the surface visible/behavioural level, look at Russell Barkley and The Occuplaytional Therapist. There are probably more/better resources for ASD too. I'm not as familiar with these.
If this is all greek to you and/or if you've read so much child behaviour theory you could open a library, but none of it actually works in practice, try starting by identifying which step you're on in Calm the Chaos. It's actually right at the end of the kindle sample, which you can read on the amazon website if you don't have a kindle.
Some of the reviews of this book say it's too confusing trying to cover too much ground with too much repetition, but I think they misunderstood what it's actually for; you're meant to identify what stage you're at, read and follow the action plan for that stage and combine with external resources, it's not really a digest this entire book in one go kind of thing (if I understood correctly anyway).
Likewise Conscious Discipline has what they refer to as a "pyramid" where you have to get the bottom layer solid before you move onto the next. Great model. It is written for teachers, but I think that's OK.