drop spindle/ball joint question

[cali_surfer]

I had a question regarding ball joints and spindles. I put drop springs on the front of my '69 about six months ago. I don't drive it that much but it needs to get aligned, tires are wearing weird. I'm broke rightnow and can't afford to do the disk brake conversion (will do drop spindles at the same time). Anyway, my question is this, since I'm going to have the truck aligned I figure I should also put in some new ball joints because the ones I have in it rightnow have torn boots, and are possibly the originals. I was just going to have the alignment shop put them in for me. Down the road when I do the spindle swap, can I remove my old spindle without ruining the new ball joints? I want my alignment to be true, thats the reasoning by putting in the new ball joints, but I don't want to buy new ones again when I do the drop spindles. what do you think?