OK KendallP Ill post an update, such as it is.
I have been running the above referenced 36 LED boards for over a year now (first batch for 14 months and the others for 12) No failures and no noticeable difference in brightness yet. Next time I am at the trailer I will install one of my unused spares in a dual fixture, and if there is a notable difference I will try to document it.
I have spent about 20 days camping since the change, about half off the grid, and the trailer has been lived in for the last two months by friends that are remodeling their house. I would place the total usage to date at about 900 to 1000 hours of on time for the most used lamps.
Dave