Air engine with 8060 prop mount

I wanted to mount a prop on the engine, so I put some screw holes in the flywheel and made a mount for the prop. It uses 3 screws and nuts. I lost the package the screws came from, but the threads are about 4.7mm wide, they are about 18mm from the bottom of the threads to the top of the head, it has about 15 mm of thread, and the head is about 8.6mm wide. The nut is abot 9.6mm from flat side to flat side, and it is hexagonal. (Thank you calipers!) Could someone that knows what screw that is comment so I can put it here?

You have to mount the flywheel backwards, and the mount will bend. My prop has A 5mm shaft whole. also, because of mounting the flywheel backwards, The Shaft is a little smaller, So you cant use the same shaft file between the builds. I found the flywheel screw a little hard to put in when the flywheel is backwards, so you may have to glue it. I found hot glue the best for this. I also had to glue the cylinder onto the cylinder screw because the threads striped out. T