I was out in Ouray two weeks ago and Moab last week. I was with a guy with a 1992 and he had some buzzing at the CC and fuel smell but was running around 210* coolant temps while mine was at 185*
We both had some smell out in Moab but it was after some steep down grade maneuvers and I attributed that to flooding the CC.
I've been doing some testing over the last month measuring temps in relation to fuel smell via Scangauge II, and I think your 185* mark is an important one (at least at Colorado elevations).
To recap, I have installed a new OEM CC about a year ago and new hoses this summer. I have never had a fuel boiling issue, only an under hood fuel smell issue during the hotter months. As far as I can tell, we have (up to) 10% ethanol fuel mixture year round.
I installed a snorkel during the testing period, which has had little effect on intake temps on the road at speed, but seems to help in slow speed or idle conditions. There has been no effect on engine cooling in normal use in regards to fuel smell.
The net of my observations is pretty simple - if I am driving in conditions where the coolant temp does not rise over 185* there is no fuel smell ever. Anything much higher than this and I get fuel smell every time with increasing duration and intensity the hotter the engine temps over a longer period of time. Max I hit was 210* on a steep uphill on I-70 at 8K feet @ 93 degree ambient temp carrying about 800 lbs of passenger and cargo, and fuel smell was very strong upon parking. This tells me my cooling system is within *normal* ranges, but not working effectively enough in regards to generating excess fuel vapor.
Today was a great example. It was ~55* driving downhill into Denver today (7,400 ft. elevation to about 5,600 over 30 miles). Coolant temps stayed in the upper 170's to lower 180's and no fuel smell when I parked. On the way home it had warmed to about 65* in Denver and coolant temps on the uphill held steady at about 190* with very mild fuel smell for a relatively brief period upon parking at home.
So I see two sets of problems - the first is fuel boiling as addressed by replacing the CC. The second is fuel vapor smell that I think is clearly caused by a lower engine heat threshold due to fuel mixtures, requiring greater cooling capacity to keep temps at 185 or below or the CC will vent the excess vapor causing in-cabin issues at slow speeds. As Rick points out, his temps were at 185 with no issues but another 80 was running 210 with a strong fuel smell. That's the cooling system, not the CC.
All of this observation is at relatively high elevation, where the problems seem to be more persistent, but it seems the underlying issue is that our engines were designed to run at temps that are higher than current ethanol based fuel mixtures can handle at higher altitudes and the solution is to optimize cooling capacity to prevent steady operating temps at 195-210* and keep them more in the 175-185* range.
. For the first time no pressure has come out after removing the gas cap for a fill-up 
