differential cover removal

The differential on my 87 300tdt has developed a leak at the rear cover, and the tech quoted 7.5 hrs to remove and reseal it.
That seems ok if the whole unit has to be removed, but is there a way to remove the cross-brace just aft of the differential to get access to the rear cover? I checked the front seal and the output flanges and they are dry. Also what kind of sealant is the best to use once it is apart?
Steve