Mark’s three rules
Meticulously plan every non-standard part that you use or make, so it looks right and fulfils your vision for the build.
Don’t be afraid to fabricate parts yourself; the end result will always be more rewarding than buying parts in or having someone else do it for you. You’ll learn new skills as you go, too.
Restore/refinish every part of the bike, even those that are unseen. Only then will it look and be truly ‘factory fresh’.