Forum OpenACS Development: Re: Issues with site-wide SSL configuration
Option (1) is where we are today and we plan to run some tests this week. If the issues persist, I think we will try option (3) next as we want to get this done as soon as possible.
We had also considered moving this to NaviServer but were afraid it would be an insurmountable task. It's encouraging to hear that it is not too much work
The link  shows the changes in packages/acs-* in chronological order (starting 13 years ago) to give you a glimpse what's needed.