You would know already if your W/D is compatible, because your primer would wrinkle or get gummy when you wipe it on. so you should be ok there. seam sealer is designed to stay flexible, and will take a long time to cure at low temps. thicker takes even longer ( like drip rail opposed to rocker seams ). I would say dont get near it with block sanding. just do the scotch bright thing. Good talkin with you yesterday, keep movin forward, and listen to the elco !
