I did notice a post from 2013 where a member posted he had looked at or purchased a ported nickel 58 sn N153xxx. Thougt that was interesting since it matches mine except for the last 3 digits. I sent him a message will be interesting to see how close they are. As for the letter we'll see maybe later down the road. Anyway if the porting is aftermarket or not I wasn't looking for museum piece, I like trailer park queens that shoot and am looking forward to it....