Time required first-time for BHW balance shaft upgrade

OilHammer knocks out this upgrade in 8 hours, but suggested (see post) it would likely take a bit longer than 8 hours on a typical car the first time a mechanic does this, with no prior experience working on the original chain modules.

Any folks that have had this upgrade done by a local garage, where your car was the first one they had done this on, how many hours did they need for the job?

Just trying to see what a realistic expectation level would be if I took it to a place that have done lots of timing belts, but never this particular procedure.

A lot will say no.

Because it'll take them 12-14 hours to do.

the first one I do will probably take longer than 8 hours, but it shouldn't be too bad.. I'll stick with charging 8 hours labor for the first one and use that as a basis for figuring out a flat fee for the balance shaft upgrade on future cars.. I'm pretty confident I can get the first one done in less than 10 hours if everyone at the shop leaves me alone..