8-1/4" rear end questions?
The axle spline count went from 27 to 29 in 97. If your rear end currently has 2.45 gears then you will need to get a new carrier in order to go to numnerically higher gears (2.76, 2.94, 3.23, 3.55, etc).
As you go numerically lower in ratio the ring gear gets thinner. For Ma mopar to offer the 2.45 gear they couldn't go thinner so the carrier was machined differently to accept a 2.45 ring gear that is thick enough to have the needed strength.
Randy's has an 8.25 limited slip center section on sale for $189 right now. If you are going to go through all the work to swap ratios might as well go for the limited slip too.