Take a profile view of the fuse with the CG position accurately shown. Position the view so that the fuse is in level flight attitude.

With the fuse in level flight attitude, draw a line straight down from the CG, then measure an arc of 15 degrees forward of the vertical line that drops down from the CG. Draw a line through the 15 degree point; locate the axle of the main gear along the line that goes through the 15 degree mark.

To get the prop clearance that you need, adjust the position of the axle along the 15 degree line.

The above works well for paved surfaces; if you will be flying from grass surface use 17 degrees instead of 15 degrees.