GM 14-bolt FF Rear End with 149k miles

Hi to all, Our TV is a GMT400 1997 GMC K2500 7.4L Burb with 149k miles. It is 8-lug, 3.73, GVWR 8,600, with GAWR RR of 6,000 lbs for the full floater rear axle. We believe the rear end also has 149...