iv done that same job you are now its a pig made even worse if you are doing it off axle stands like i did took me hours ...
i dont know if you read but i changed my turbo at the weekend and thought here we go with the exhaust again but took me about 2 mins to get off and put back on so easy from above .. i know it looks like a lost to take out but it dont take long take the inlet off it should be 6 alan key bolts also the air pipe from the box , and its all there easy as you like .
i think its better to go that way at it now than snap or screw up the studs in the outlet manifold ..
if you still cat shift it from above cut the stud level with the nut then cut a good grove in the nut and stud and get a screw driver on it or better a impact driver , hopefully you will bring the studs out with the nut and then just replace them . hope this helps