"I don't have the new 13 inch spinner or backplate yet, but just had to look over my new cowling. First off you need to cut a slot for the nose gear to slide into, and a hole for the muffler. Then of course you need to cut out the area where the prop drive sticks thru. This is just a first setup looking for problems, the top is riding up on the canopy arms, that is why there is such a gap at the firewal baetween the top and lower sections.l. All in all, I think it will be a better fit and look much better than the old one, affectionately referred to as the ""belluga whale"" model due to its blunt nose."
