In post #19 you said you want a locker for the Dana 30. There were lockers made for both the iron case IFS (a LockRight lunchbox locker was available) and the Dana 30 has there own. The aftermarket Dana 30 that you've been eyeballing is a shortened Dana 30 with a early bolt-in style IFS axle from the short side of the S10 diff for the short side of the Dana 30. You might be able to make your own a lot cheaper than buying it if you have the machinery available to you or a machinist buddy.