That PDF looks very good, ill have a read through, heres a timing diagram I did when we tuned his TR6 with a radical cam, he had it a fair way out.

I have a TR6 engine for my Spitfire and that has the same timing error, not from the factory but that someone has put in at a later date.

What is the "OP" where things reside? Sorry if its a basic question...!

Cheers
Kevin
TR6 INJECTION TIMING V3.jpg