Don,t be too harsh on the guys taking 10 hours for an MEC change...thats about right, next time you get a chance have a look then do so. GE hang the MEC,s from the roof of the factory and then build the engine around it. With regards HAECO record, I personally have witnessed a 524D4 engine change take 3 hours but be aware, a 524D4 drop,s off the wing as a whole unit with no complications wheras the 524G is a different beast and takes much longer and then theres the C and D ducted engines like CF6, Trent 700 and 800 that take forever....sometimes 24 hours.