Bend the fourth diode into a "U" shape with the lead from the silver banded end bent 3/8" from the body
and the lead from the black end bent 3/4" from the body.

Insert the lead from the black end into the power transformer terminal 4, solder and trim excess.

Insert the lead from the silver banded end into the lower hole of C5, solder and trim excess.

The red and black heat shrink does not come in your kit. I added that for extra protection from shorts.