MacOS – Replace dead keys of default US keyboard layout on Lion

I've been trying to create a new keyboard layout using Ukelele on Lion. I want to replace some dead keys combination like option+e to option+'.

Ukelele seems to be the right tool for it. Problem is, since Lion, it doesn't support the "New from Current Input Source" option, which means I can't seem to simply edit the "US" layout to replace the dead keys I want.

Is there an already working keylayout that works on Lion and replaces the option+letter combinations with option+accent?

Is there another solution for this problem?

Where can I find the original Lion keylayouts? I've tried using old keylayouts (or automatically generated ones), but then a lot of subtle things breaking (like text selection on textmate).