When i got my car, it came off the boat with the stickiest glue i have ever seen. It was in the shape of a big X in the inside of the windscreen. It was thick too, like about 3mm thick of hard super glue.
What i did was put some grease on the X the then got a razor blade tool that is used to clean stove tops.. and scrap down a layer of the glue.. at the same time i rested a towel over the dash, wheel and seat to catch all the debris.
Then i got eucalyptus oil, and put on old towel and just rubbed and it cleared the glue off no worries.... no scratches at all.... really effective.
Stay away from steel wool i think.... My friend had the same glue on his car, but he used one of those dishpads (dosnt feel rough to the touch) and it has severly scratched the windscreen.
Im sure eucalyptus oil will do the trick.