2001 Chevy Suburban leak on cargo floor after long drives w

I recently had my fuel pump replaced which required the removal of my gas tank. Ever since then after long drives 6-8 hours with the A/C running in 90-100 degree air temps (also humid conditions) I have a very wet spot on the cargo area floor just behind the third passenger side seat. I suspect a blocked condensate line is redirecting the A/C condensation into the vehicle instead of outside. Could this be the problem and is it possible for me to check it myself somehow and unblock it? I was on a car trip over 600 miles away when I had the repair done at a Mr Goodwrench shop. I can't easily just take it back in for them to take a look.