boardingnath997 said:
Last night I took the wheels off and put a liberal amount of grease between the re-used shims and pad thinking that this would be the cause)
New shims come with a self adhesive pad which attaches to the back of the brake pad, ie the shims work by being stuck to the brake pad not slipping against them. Don't know if it will cure your issue but if you clean up the shims and backs of the pads and use a spray adhesive to attach the shims to the pads it may help. Incidentally I made the exact same mistake when I changed my pads last time before I was helpfully corrected by my local Indy