I've done it and it fits and sounds amazing.
Putting it in is a trick. Look online for how to swap a speaker out in that amp. It is tight in there and you have to pull the chassis...that is the only way to make an E-120 fit.
But it is easier than it sounds to install.
You will be very happy with the results. It is Jerry like.
Make sure the boost button is depressed. It helps you get closer to the sound you seek.