Valin - How about this?  Figure out the difference in pitching moment caused
by the heavier engine.  Then figure out the difference in tail down-force
required to counteract this higher pitching moment.  You can probably assume
the CG stays in the same spot, since the moment arms of the engine and tail
are large compared to the CG shift.  Now, knowing how much extra downwards
lift the tail needs to produce, you can figure out how much extra incidence
the tail needs to have at cruise.  Use the classic L = Q * S * CLalpha *
deltaalpha.  Deltaalpha is now the required change in incidence angle.  FYI,
the tail is a NACA 0012 airfoil, as I recall, and even if it's not, using
2*pi per radian is probably close enough for CLalpha.

To the LNC2 dual rudder pedal crowd -- Concerning rudder cables, Don Goetz
told me to run two sets of cables and have both cables be directly attached
to the rudder.  In this manner there are no nicopress sleeves buried in the
tailcone, and no drag on fairleads either.  In the classic Don lingo, he said
"I don't know why Lance designed it thay way -- I told him it was stupid
fifteen years ago"

Too bad he told me AFTER I had already built it per the plans....so I kept it
the way it was.

One thing I did, however, is follow some good advice I got on this forum.  I
think it might have been from Chris Zavatson but it might have been from Dan
Schafer (anything either one of them says is worth listening to, IMHO).  I
took my adjustable rudder pedal assemblies, ran a short length of cable thru
them, and had a turnbuckle fitting swaged onto the aft ends and a clevis
swaged onto the front ends.  The clevis goes to an eye bolt on the firewall.  
The turnbuckle attached it to the cable running back thru the tailcone.  In
this manner, the turnbuckle can be disconnected and the rudder pedal
assemblies can be removed from the airplane.

BTW, one can compose quite a lenthgy message at work, and it looks like
you're actually working....

- Rob Wolf
LNC2 MkII IO-360