I have been working on the installation of the vertical stab. Per Drawing 78 I trimmed the VS 702 9/16 of an inch and installed the F884 attach plate and F885 Spacer. The Aft holes are drilled dead on the drawing dimensions and when installed the Stab is perfectly vertical. I however have an interferance problem when re-installing the vertical stab after the aft skin is installed. The forward edge of the VS contacts the skin and the lower bolt holes in the F884 attach plate are still off by more than half the hole diameter...obviously something is not right...should the forward point of the vertical stab be trimmed to remove the interferance? Has anyone encountered this problem?