[UA] UA magick in the OtE universe

[Rev Kev]

Hidey ho, I thought I'd pick your brains a bit.

I am running an Over the Edge game, but I incorporate some
tasty UA bits in there.  I am introducing postmodern magick
into the universe.  In essence, it'll be a war between the
traditionalist ritual folks and the
get-something-now-for-only-a-small-piece-of-your-soul new
dukes.

Well, I'm trying to think of a way of using this magick in
the OtE-verse.  I'm going to keep the charge system, of
course.

I'm thinking that if someone is not rushed and has the
charges, he can just expend the charges and do the magick. 
Like, say a cliomancer taking off an afternoon to rewire
some history.  He's not rushed, and eventually he's going
to succeed in his skill since failure does not cost charges
(except for BOHICA but I won't incorporate that here).  But
if he was in a stressful situation--such as convincing the
satanist in front of him that it was someone else who broke
his ribs 2 weeks ago--then he'd have to roll his skill to
get the spell off. 

But how to determine the difficulty?  I thought I'd see
what you folks thought.

If you don't know OtE, you could still help me out.  It's
pretty simple.  You roll a number of d6s based on your
skill.  For magic, a beginner rolls 1d6.  Someone with some
training can roll 2d6.  Getting into 3d6 and higher is some
pretty major stuff.  

What wouldy you do in this situation?

I'm thinking of having a minimum requirement.  Like you
have to have at least 2 dice to do sigs and at least 3 dice
to do major.  

Kevin