Specific steps to replace (outer) side windows - de-rivet?

[n86121]

Side windows all replaced (front was done some years ago).

Total time from the the shop on field:

1. Remove all side windows, inner and outer
The pilot side emergency window required extensive de-riveting etc.
Most windows required some trimming

2. Replace all gaskets and seals, inner and outer, and

3. Re-install,

...was 50 hours.

The fellow was also dealing meticulously with any corrosion he ran across.
He had to clean out some corrosion and treat, replace some tabs that broke, etc.

Any reality checks out there on it being a 50 hour job?

Thanks