The right size, width, thickness and weight of a dowel rod will work wonders...closet pole, weighted PVC pipe, metal tubing, etc....in a pinch you can use a broomstick...
and that stuff smelled horrible too...We outsourced our flow on tint for rear windows to another shop (Honolulu 1985) and I had to drive it back to our shop for the customer: very old Porsche, NO A/C ! every stop light i opened the door so I wouldn't pass out from the smell... fun times...