This installation is for HO-Scale Athearn F59PHI uses TCS A4X Drop-In decoder and was performed by TCS Customer.
TCS A4X -working front ,rear & ditch lights fits as shown in the photo's
Remove the motor from the frame while it is out insulate with tape the bottom of the frame. remove the contact strips on the motor very carefully so has not to loose the brush springs.
On each these strips solder wire just long enough to be connected to the motor tags on the DCC chip.
While the motor is out of the frame remove the trucks and after removing the truck side frame ,remove the wheels and gears.
Next solder a wire to the metal sides of the truck in fact for one side you could use the metal prong for the old pick up system.
Assemble this all back together wire to the A4X as per the instructions that come with the A4X.
For working lights I used 2mm tower LEDs you will need to cut the plastic at the front a bit for clearance but once the body is back on it won't be noticeable.
The ditch lights are again 2mm LEDs and wired to the purple and green solder pads on the A4X with the other wire from each LED solder to the BLUE (light) wire tag.