Can After tax contribution to traditional IRA be returned?

Hi everyone,

 

I made an after tax $6000 contribution to traditional IRA account and want to convert to Roth IRA, but the pro rata rule makes the $6000 almost fully taxed again. So I would like the contribution to be returned to my non-retirement account? 

 

Can I use  "return of excess contribution request" for to request the return, even it's not excess contribution? I know I will need to pay tax on gains, I wonder do I need to pay tax on the return of the $6000 (it's after tax money).

 

Thanks for your help