The ring gear bolts changed in I think 2001. In 1999-2001 or so, they were 3/8" bolts and then went to 7/16" bolts. Almost every part place I've run into doesn't know that there's a difference. At least this was the case with my rear Dana 44A. I'm not sure if this applied to the Dana 35 or not, but sounds like this is your problem. I would return them or you will need to tap/drill out your carrier and ring gear.
2004 WJ 4.7L, 1959 CJ-5, 1990 XJ Limited, 1996 XJ (sold), 1989 YJ Wrangler 4.2L (Sold)