i recently tried to remove my turbo what a pain it was bolts breaking off water pipe fixing bolts snapped off in the end i decided to remove the lot off as one piece got all the manifold bolts off then came to the two bottom ones in the middle i couldnt find any spanner to fit so i got an old 13mm spanner put the gas torch to it & bent it to the right angle and got them off. it was a lot easyer to dismantle on a bench no back ache but still ended up drilling and tapping out some of the other bolts on the manifold.

best of luck mate.