2004 Meridian/Journey Cat Eng thermostate (regulator) replacements

[wagonmaster2]

Has anyone replaced the engine thermostats on their 2004 model Meridian/Journey 36' Cat 330HP engine? I raised the bed, removed the large metal plate covering the engine, but could barely see the rear of the engine let alone where the thermostats are.
Does the mattress & bed platform have to be removed in order to get to the smaller metal plate clear to the rear of the coach just under the head of the bed?
What sounds like a simple job is starting to look like a major dismantelling project. Our bed is the numbers air mattress so that seems to complicate things even more. No wonder RVers go for the side radiator on their DP.
Thanks for any help/suggestions. If I decide not to try this project myself I could at least get some things out of the way for the technician and save some hourly charges.
Wagonmaster2
2004 Meridian 36G Cat C-7 330 HP