I'm getting ready to reinstall the windshield on my 86 GLHS. I found a now obsolete install kit ( mopar 4057957 ) I guess this kit uses the old butyl seal that I would rather not use. I would like to use urethane ( I've done plenty of windshields at the dealership) Is there a shim kit or does anyone know the spacer thickness so I can sent the glass in at the correct dept? any other tips would be great.