I know it is frustrating when you ask a spacific question on a spacific trailer and you get answers such as this but for what it's worth.
I have a 1980 Boler
13 ft and have a rather large AC unit in roof, Colman 1200... Every one on the RV sites said I was crazy and it wouildn't stand up but the unit was in place when I got it in 2005 and the unit was installed in FL ( we are in Maine)Year of intallation unknown.
After getting so many negative responses on this and another site, a RV dealer told me that all trailers built in USA and Canada were built with the structual integrety to handle a small unit. (this got many of GA-FAW from many members also.......
After wintering with a post inside under the unit to support added snow weight
, and useing all last summer original 1/2 sag has not gotten any worse and no signs of stress cracks or leaks
in fiber glass.
Colman makes a unit, I believe is a 700 slim-line with weight
of around 98#
Gerry teh canoebuilder