Question about upcoming BB interview

Last Thursday a BB invited me to a phone interview within S&T for Sales - I was excited for the chance at a FO gig and immediately said I was in and let's schedule which was done so for first thing tomorrow morning. S&T is a distant second (or possibly even third) for me and really only within the trading side or maybe something that could get me to a Capital Markets Group and then to IBD anyway. As many people have mentioned here, few people probably have interests in both S&T and IBD. Honestly, I just think Sales is way out of my wheelhouse and skill-set.

Friday morning I decided to just remain candid with everyone and I emailed the recruiters letting them know I was thrilled for the opportunity to move forward, but had to be honest about not feeling like I'm a fit for Sales. I essentially asked if they'd be interested in interviewing me for IBD or perhaps some other element of S&T.

I haven't heard back yet and as far as I know the interview is moving forward on schedule. Question is how do I approach this MD in the interview without him feeling confused as why he's even on the phone with someone uninterested in his team. The initial invite did say that candidates may be considered for other areas of the bank depending on the conversation. How do I play this? Do I tell him right off the bat or get through the resume questions and then when he asks about Sales bring it up? I'm sort of hoping for HR to get an email to me in the morning, but with this being first thing I need to prepare for that not to happen...