Ball joint differences

[Rusty Wrenches]

This may be an odd question or not. What are the specific differences between 73-87 and 63-66 lower ball joints.

Reason: Got a good deal on some porterbuilt stuff and it came with the Mcgaughy's big brake kit. I dont have wheels big enough to fit over the brakes and I just want to be able to get everything together to be able to roll it out of the garage. So Im planning on just installing 63-66 lowers into my porterbuilt arms for now... but i was curious to know that differences.

[Hart_Rod]

I believe they are smaller.