Planning a very long ride - 8 hrs

I'm toying with the idea of doing a long ride this fall, after a summer of
400 mile/months, and I'm interested in some ideas as to pacing. Here's
something I've been thinking about:

Ride for three hours, then 30 min rest (and take a shower?), eat, then ride
for 2 hours, repeat rest, then ride for an hour, repeat rest, then ride
final 2 hours. Does that seem like a good scheme? 3-2-1-2?

People who do touring and stuff ride about 8 hours a day for like 2 weeks.
'Course they're sightseeing so it's more fun. It would probably require a
"support crew" to bring food and change of clothes and stuff. If you were
gonna do it how would you break it up?

I'm thinking the mental aspect would be the most difficult. Gonna try and
get the family interested in it to help with that.

I'm sure some here would say 'just ride for the 8 hours, what's the big
deal', but that would be OK for those who have ridden a lot (like frequent
3-4 hour rides), but my longest ride has been 3.5 hours, and only did that
once. I'm hoping to get some posts on others who have done something like
this, and their experiences vs the initial expectations.

I plan to start the ride early in the AM, like 5-ish, or first light.
o 5:30-8:30
o 9:00-11:00
o 12:-1
o 2-4pm

TIA,

-Badger