Finally found how the exhaust fumes were leaking into the car

Have you not seen my Avatar? Top down 24/7 365, drive it every month in the year, Northern Colorado! No gas fumes issues!

BTW with the heater on other then "off" cowl air is forced into the car and SHOULD create a positive pressure in side the car keeping any exhaust gasses out.
You remind me of a guy I used to see back in the '60s that rode a huge Harley in the snow/ice. He would have his legs out spread-eagle like outriggers half the time.

I love having the top down enough that I wired in a plug for my old 12vt heated motorcycle jacket for the little woman. And I plugged the floor output of the heater that blows on the throttle pedal. Then the wife can have the heater on MAX without roasting my right foot.

For the fumes, I tried a lot of combos of wing vents, heater blower, etc. without success. I do still have some small gaps between the convertible top frame and the top of the side window glass. Man, I've worn out pages in the FSM on convertible window adjustment. It reminds me of women giving birth. After I forget the details of the last attempt, I optimistically go back for another go. at it.
:BangHead: