Early vs. late control arms

[gringoloco]

All thing being equal i.e.: spindles, springs, brakes, etc.- if I swap my early(71-72) control arms out for late(73-87) arms, will my alignment be affected?

I know the upper balljoints are a different diameter, but will still bolt in place. The shaft pivot points will obviously be the same, but are the balljoint distances from the shaft equal? Also, is the bottom of the spring pocket on the same plane; given the same spring will there be more/less drop with one or the other?

The obvious answer is: "Just go get it aligned". Just want to know if I can bypass this.

Thanks -Chris