if you have an SYE and CV driveshaft then get rid of the t-case drop, then like Jeffy said align the diff yoke so it's inline with the driveshaft (or slightly under and not over). If you don't have a CV d/s then i suggest getting one (otherwise it kind of defeating the purpose of getting an SYE.
for setting the angle on a non CV d/s you need your diff yoke at the same angle as your t/case rear output yoke, otherwise you'd get major vibrations, i had the same thing happening when i put a t-case drop and had to change the angle shims).