First I measure the angle from the face of the relfector to the side of the under cowling.
I then marked this anlge on the signal housing and cut it with a small hand saw.
I sanded with some aluminum oxide paper and checked it against the original angle.
Next was to put the mount back in the housing and cut it.
I had to drill out the hole to fit the threaded piped I used for the new mount.
Here is an original and a modified signal.
On the left OEM install and on the right new placement.
A couple more pictures of the final installation.