i had to use mole-grips on the heat shield bolts. the manifold to head studs and nuts should come off easily as they turn into bolts if rusted bad.
i had to angle gring the cat bolts off, then i drilled the cat out and used 10mm bolts and nuts to secure it.
the bolts with springs on (front cat to front/down pipe) may be ok, but i snapped mine taking then off, but i had a spare standard manifold so it didn't matter to me.
