Someone asked Rav Shlomo Zalman if he should wait until after Tisha B’Av to follow up on a proposed shiduch. Rav Shlomo Zalman held his hand and said he should even meet the girl on Tisha B’Av if necessary. During a walk through the Shaarei Chesed neighborhood Rav Shlomo Zalman stopped and pointed to a house and commented, “In that house lives a tzaddik who met his wife for the first time on Tisha B’Av.”
Regarding the dress code for a date in the nine days, Rav Shlomo Zalman advised to wear a nice jacket but not shabbos clothing. (Aleihu Lo Yibol OC 314-315). Revach.