I'm looking at a used 3.7 to put in a quarter scale Waco, but don't know if it will fit inside the cowl. Based on the dimensions D&B shows on their website, the engine should fit using 10mm plugs. The cowl has a 10.25" inside diameter. Can you guys that own the 3.7 let me know if you think it will fit? What are the sizes of your cowls? BTW, do you have any for sale?

Chuck