The temperature reading is going to depend on probe placement. Just a second, they are using the same thermostat? That is the problem. I think it would be very hard to make sure that both temperatures are the same that way.
There are ways to bring down your temperatures maybe....like you said, lifting the tank a little. You could lower the thermostat, putting one tank at about 85 and the other at 95 ish? You could remove the uth from the glass perhaps?

Ok, lets be honest here, I am not being useful. I'll let someone else take over.....