71 hemi orange swinger rescue.

Possible, sure. Hard to get to the drains with the fenders on. Make sure they're not clogged. Blow, suck, blow suck. Go up through the vent holes (heater box and vents out) with homemade attachments for a shop vac. People even cut access holes in the firewall like the earlier cars had. Or tow it about 60 with the vents open!
I know the inner cowl has tons of leaves in it. Will try that first.