Was having my back glass replaced today and when the installer got the old one out,of course there is some pretty good rust inside the channel where the new glass will sit.He did not put the new glass in. Told me to get rid of the rust and prime it and he will come back.Some pitting in some spots, but no holes anywhere.Is it ok to put Por-15 on it? I know not to get it on the area where the new paint will be seen.The installer wasn’t sure if the new sealer he puts on will mate with por-15.