Car Seat Naps

My 11 month old has been falling asleep in the car seat on the way home from his swimming lessons. We live in a cold climate, so he wears a snowsuit in the car (not for long drives, but this is like 15 mins), so when he falls asleep he is all suited up.

Naps in general are a huge struggle, so fully removing him from his seat is not an option if we want the nap to continue, and we recently went down to one nap, so ideally it would continue. That said- we worry about him being in a snowsuit indoors. I can remove his hat/hood and unzip the suit over his chest to be a bit less warm... but I'm not sure if that's still too warm?

Thoughts?