I bought this screw on motion detector but it was too long and the light bulb ended up outside. also the frosted glass of the fixture blocked the sensor. so i decided to modify it so the sensor can be outside. this is my first instructable and it was actually harder than i tought to document every step. i hope that helps anyone that faces the same issue.

Step 1: Tools Needed

safety goggles (very important)
a motion detector light add-on
electrical wires
soldering iron
glue
dremmel (anything that will help you cut through plastic)

Step 2: Preparing the Motion Detector

cut the motion detector in three different parts:
the part that screws in the electrical light socket
the motion dectector
the socket for the bulb

Step 3: Extending the Wires

in this step you will need addtnl wires to use as extension. i used a soldering iron to attach the wires together.
basically you use the wires to extend the wires you just cut in step 2.
extend the wires from both the electrical and bulb sockets.

Step 4: Attaching the Light Sockets and Prepping the Motion Detector

in this step, i atached the light bulb socket to the electrical socket and prepared the motion detector.
i used the existing holes in the socjet holder to pass the wires to the outside.
depending on which motion detector you have, i had to open mine to have the output wires come out the same hole of the input wires.

Step 5: Attaching the Motion Detector

in this step, i connected the wires from the electrical socket to the input of the motion detector, and the outputs of the motion detector i connected to the light bulb socket. make sure you maintain polarity.
after this step, you re basically done. all you have to do is wrap up everything tightly using electrical tape.

Step 6: Test It Out

all you have to do now is test it out and find the perfect position for the motion detector.
i know i could have bought a light fixture similar to the one i have that comes with motion ddetector, but they are pretty expensive. this one works fines, plus its very versatile since i can move it to any light.