Although it's been several years since I did the install, with help from my very good mechanic friend.....
It took us about 10 hrs total IIRC. But a good chunk of that time, involved us going slowly & me documenting each step of the process in order for me to author a detailed "How-To" install tutorial.
If your shop hasn't performed this install before, or not on this platform, I would say 8-10hrs is on the upper end(s) of the install range.
Factor in your shops per labor hours charged, & I think you're within reason on that quote.
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