You can always refer back to the microfiche online to get proper method of assembly. Also, these days, you can snap some phone pics as things are before disassembly, & during disassembly, & do 1 at a time if there are two, so you can resort to looking at the intact one for comparison.
My method of bleeding w/the caliper & 1line @ a time off the bike would have shown you the components were OK, but you had an air bubble at the top of the caliper body. Still you would have to have the master cyl assembled correctly. Read the online microfiche.
Be sure to treat Dad to a good meal of his choice. Barbeque season!
Glad you got it done?