The gyralite assembly is shown here as a "test-fit". The whole assembly fits snugly into the nose.

Next steps include:
1) Paint the assembly before final installation/glue-in.
2) Also, a little more notching of the nose under the gyralite assembly still needs to be done.

Since this photo was taken, both the 5506 and the 5507 now have the gyralites installed.

For details on the installation technique, see the tutorial below from my friend - Paul Ellis - who introduced me to this technique:
http://www.pbase.com/sp_8299/sd50_nose_lights