Drhulee,
If there are tubes in the strap, and you have taken them out but the strap is still too large / thick due to lack of skivving, give this a try.
CAUTION - REQUIRES COURAGE, SOME GENERAL KNOWLEDGE OF POWER TOOLS AND A DRILL (ALCOHOLIC BEVERAGE OPTIONAL).
Take the tube out (if there was one in there in the first place), and take a drill bit of similar diameter to the lug hole / tube hole in the end of the strap.
Once you have the drill bit size established, chuck the drill bit firmly, and then place the strap on the drill bit. Hold the drill between your knees (facing away from you), and with one hand, hold the strap by it's end with just enough pressure to keep the strap under control, and with the other hand, slowly energize the drill just enough to create a "bite" with the edges of the drill shaft eating away at the inside of the strap.
Keep the drill as firm and safe as possible, and slowly, with out putting outer pressure on the strap sides, slowly erode the leather from the inside of the strap. But you must not rush, and take itsy bitsy turns until you get the strap where it will fit.
I have done this before, and will work, but it takes a ton of time and a great deal of anxiety. Afterward, just re-coat the edges with some edge dressing, and you should be GTG with a strap fitting on the lugs.
Just make sure the drill bit you are using is no bigger than a tube that would come with the strap, and use the drill on the "tourque" setting, not the "drill" setting (if your drill is so equipped). Otherwise, just go slow.
Good luck, and pm me if you have any other questions.
S/F Marty