Was reading about how to attach the engine mount to the engine ring frame. The instructions want the bolts cut off so that a minimum of two thread are visible beyond the nuts. Since it is physically impossible to cut the bolts after they are installed, I will cut them before. Measured the width of the mount fittings – 40 mm. Measured the width of the ring frame fittings – 40 mm. Measured the thickness of the nuts – 9 mm. Measured two threads – 3 mm. 40 + 40 + 9 + 3 = 91 mm. Cut a length of tubing to 91 mm to act as a gage and used it to cut the four bolts to length.