I really regret what u went through brother! Ok some mechanics do not have knowledge and are eager to learn, but some think that they have divine knowledge and experience which makes them intolerant and closed for anything new...
as a small example in 2001, i remember that putting back the cam of 1hz, the mechanics used to apply all the power they could muster to those poor 14mm (if im not wrong) bolts!
Later in the workshop-manual I found out that only 45Nm torque needs to be applied!!
Long long long story cut shot, I fought long and lot, just to get them to follow that whats written in the manual (even tough it was my money, my cars engine my risk and all) and even after supplying them with a simple torque wrench! They said that they gave no guarantee if it would work, and everything would literally fly-off (as if they guarantee it otherwise)
I had to end up extremely nosy, pokey, and the most hated, even tough all of them are good acquaintance of mine!
in the end, I put through what i wanted, and the engine was just wonderful, and runs till today...As for them, even after all these years, they still havnt moved an inch forward!
