Alignment Question Related To Tires

[scchang]

I'm having front control arms replaced and alignment done on 01 4.4 w/sport and 19s. The front tires are badly worn on the outer edges as a result of worn control arm bushings. Does it matter if I have the worn tires still on the car during the alignment or should I have the tires replaced first?

I have a set of 18" wheels/tires that I run in the winter. If I need to have good tires on the car at the time of alignment, is it okay to have the 18s on the car even though most of the year the 19s are on?

Thanks for any help!