If something went wrong with your order — the file did not arrive, the download will not open, you were charged twice — write to Gumroad support from your receipt email first. They hold the order record and can fix delivery problems fastest.
Reader questions, corrections and “here is what happened when I used the counter script” stories are read personally. Leave a comment on any video on the channel and mention that you bought the book — that is the fastest way to reach me.
For anything else, contact us through the same channel. Please do not send vehicle-specific repair questions: I cannot advise on a car I have not seen, and Chapter 27 explains why that line matters.