I have used the Canton CTR-20-930 windage tray on three builds to date, and I used the Milodon 81167/Moroso 38192 351W stud kit on two of the builds.  You do not have to use a spacer with the 351W bolt kit.  There is some trimming necessary to fit the Y block oil pan rail and the mounting holes need to be moved to fit the spacing of the Y, but easy to do with simple hand tools and a cut off wheel.  I will try to show the areas needed to trim for use on all but the Thunderbird pans.  Joe-JDC

JDC