I had a similar problem. I just opened up the front of the cowl where the engine shaft passes through. I used a slightly larger spinner to hide the discrepancy. Now the front of the cowl is parallel with the rear of the spinner. This is my second Ucando and I had the same problem on the first. BTW I am using an OS 91 Surpass pumper. FYI to counter the slightly nose heavyness caused by the OS91 pumper I mounted my 1500 NMH battery in the fuselage 2 inches behind the trailing edge of the wing. Balances right where I want it. Hovers nice and steady.