3 1/2 yr old screams when getting dressed

[rhaea]

I have 3 children ages 6, 3 1/2 & 18 months.  My oldest and youngest are very high maintenance children and my middle child has always been layed back.  However, now every day when she gets dressed she ends up spending hours - yes hours - procrastinating, crying complaining, screaming about her clothes.  We have tried having her pick out her own clothes, having her get dressed at different times, punishing her with time outs when she doesnt get dressing in a reasonable time or with too much fuss, ignoring the behavior all together, etc, etc.  My patience is gone and often I end up dressing her while she kicks and screams because we need to get somewhere and letting her have her way is not an option.  I have threatened to send her to school in her jammies.  She could case less.  I recognize she wants attention.  There is no pattern to which clothes bothers her - could be her favorite outfit yesterday or tomorrow, but today she screams because it feels funny or she doesnt like it or its too small or too big.  
I know she does this for the attention.  She is easy going and doesnt get as much attention as her siblings because she's never needed it.  That being said, I know this is her way of telling me she needs it.  I have even tried rewarding her when she gets dressed quickly and easily with extra mommy time and special activities.  But nothing seems to work.
How can I get her to just get dressed without a hassle before I lose my sanity.  The whole family is becoming aggitated by her hysteria.