Basically I have 2 macros setup (and they are not optimized).

Wrath:

Code:
/script UIErrorsFrame:Hide()
/use 13
/use 14
/script UIErrorsFrame:Clear()
/script UIErrorsFrame:Show()
/castsequence  reset=5 moonfire, wrath, wrath, wrath, wrath, wrath, wrath
Starfire

Code:
/script UIErrorsFrame:Hide()
/use 13
/use 14
/script UIErrorsFrame:Clear()
/script UIErrorsFrame:Show()
/castsequence  reset=5 moonfire, starfire, starfire, starfire, starfire, starfire, starfire
I have mouse button 4 (I use a 5 button mouse) with ISBoxer to swap cast bars when I press the mouse button, and switches back when I do it again. One one bar I put the wrath macro on button 2, on the other I put the starfire macro on button 2, and then I just spam, clicking my mouse button when eclipse procs.

Normally I just use the wrath bar for trash, but I switch as eclipse procs for boss fights.