pinion seal install question

[godstangit]

well after a couple of months of procrastinating Im finally going to change the leaky pinion seal, its gotten real bad and 90wt. all over the flowmasters. Im wondering how much of a b**ch it might be to break the pinion nut loose with a breaker bar? its torqued down to 140ftlbs. and want to make sure I can crack it loose, given the fact I'll be on my back. A shop did the gear install 2 years ago and I dont think it should've blown so soon,regardless its not going to be warranteed, and what about the crush sleeve, can I reuse the old one as long as I tighten it to the proper pre-load? Any helps appreciated