Thank for all of your replies. Appears the orig builder did do a proper full flow mod. However, for whatever reason, enlarged the rear(drain) hole from 1/8 to 1/4, rather than 3/8 as many noticed. And drilling that out and retapping ( although a pretty easy job) would be difficult removing ALL the chips So I guess ill just roll with it and hope flow and pressure are adequate.
Thanks again for all the help
