I think a lot of people will believe it's a foregone conclusion that ALL w124 evaps WILL leak and that's the source of the A/C woes, when in fact there are plenty of other components that give up the goat early and are the true culprits. I was in my indy's shop a while back and looked at the carnage that was an evap replacement, he said it's at least 12hrs if you have done it before AND nothing breaks and/or gets stuck, but even with experience he said it's likely something will break and the dash will have some defects when reinstalling, so tread lightly.