Will the Edge Juice/Attitude operate without the EGT probe installed. I would like to install the E/A now and put the EGT thermocouple in later on. Truck is still pretty new and I don't want to do any permamnent mods yet. I do pull a fifth whell (9000lbs) but mostly flat ground here in Fla. Any help would be great.

I run mine without the Egde EGT probe connected as I have manual gauges.

It will operate without the temp probe installed. It is not really that bad to drill and tap the manifold. And you can plug the hole with a common 1/8 NP plug, so it is not really permanant.

I wouldn't want to tow that trailer with the edge set any higher than the tow mode, level 2. Maybe not even that setting if you are pulling long grades. It can get hot in a hurry.