Oh, the joy!  I just went through this whole ordeal too.  I was able to
get my front manifold off with some patience, WD-40, lots of cursing,
and more WD-40.  It helps if your heads have been done recently, to get
those bolts off.  As for the bolts that mate to the 2-1 elbow and
beyond..... Harbor Freight sells a cheap 4" grinder!  I also second the
use of PB Blaster, I just can't find it in my local.

 

Andrew