[Edit] I think I misunderstood. Reviewing your previous posts, I see that you rolled over to the 403(b) $2,500 of which $1,500 was basis in nondeductible traditional IRA contributions. The $1,000 of pretax money can stay in the 403(b). Only the $1,500 and gains attributable to the $1,500 need to be distributed by a return of excess contribution. You, could have the entire amount distributed an then roll back the $1,000 and any gains attributable to the $1,000, but distributing that portion is unnecessary.
