[ http://www.twinturbo.net/nissan/300zx/forums/main/view/1082860/Removing-precats-with-transmission-still-in-After-months.html ]I've done it a few times. Need stubby wrenches. If your heat shield bolts are seized, good luck to you!!! I suppose if it would be really difficult for you to drop your trans due to lack of workspace that you could give it a shot, but hands down it is easier do do with the trans out. Make sure you get the downpipes torqued properly, don't want a leak at the back of the turbo that you would have to go back in after to fix!!
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