my strangly easy u-joint change and question

Today i changed my first u-joint at a knuckle. i have changed shaft joints before but never one at a knuckle. after reading several horror stories here i was prepared for the worst. we decided the best plan of attack was to remove the hub with the shafts for a couple reasons.
1) didnt have a socket big enough for the hub nut.
2) didnt have torque spec for hub nut.
we just removed the 3 bolt that hold the hub to the knuckle. gave it a little spray of WD-40 at the seam and busted out the air chisel. within 20 seconds we had the shaft out. i had the u-joint from the local parts store. we get the old one out and grab the new one and the caps are about 1/4" small in diameter. it is now 8pm so we run into the city to autozone. they look it up and I buy a different one. we get it home and it is the same size as the one from the local parts store. we found one that my buddy's dad bought by mistake, low and behold it is the same size so i bought it off my buddy for a couple of cold beers. :cheers: so now i am all confused :confused1 about what joint to buy when i need to do it again. I have a '96 sport with a 4.0 and no anti-lock brakes. i told both places that i needed a spicer 297 u-joint and they said that that doesnt matter because every manafacture has different numbers. so i ended up with a "super strong 371" i think. the orginal i got from both people was a "super stong 365" and i dont remember what the final one was. so if anybody can tell me why two places gave me the wrong joint or what i need in the future it will be deeply appericated.

thanks
skog

The earlier XJs used a smaller u-joint -- I think it was a 260 but it's late and my brain is fried. Obviously, the sales clerk behind the computer didn't know anything if he/she said all years are the same -- they ain't. To make matters worse, in some years the XJs got the wimpy joints but the Wranglers got the good ones.

At a guess their "365" = Spicer 260, and their "371" = Spicer 297.

i just went and returned all the too small joints. i ask the guy what fit the one we found and he said that was the joint for jeeps with ABS. I was like but i dont have ABS. does this make sence to anybody why i have ABS shafts and joints in my jeep but no ABS. I actully perfer it this way now because the joint is bigger so it is stronger and i like regular brakes better than ABS everyday of the week and twice on sundays.

thanks
skog