This is a detailed enhancement for similar platforms already for sale on my . One customer that is super detailing his F units ask if I could make a slight engineering change to this part in order to accommodate overhead lighting for the EMD trucks. For sale here is the modified platforms with the LEDs that can be wired in the model for night operations on the layout. The cut or recess in the platform enables the PC board to embed and hides yet does not interfere with mounting the platform to the body. Only the LED itself faces downward toward the rails to project light onto the truck frame. The following paragraphs below is my description from the other platforms for sale on . Included will be the 4 LEDs. Rummaging around the model shop I decided to see if I could pull together enough left over parts, components or off falls to build a diesel engine. Having the shell of an All Nation B Unit and little else to go with it, and with the intent to use a set of EMD "Blomberg" trucks, I needed to replicate the platform that mounts up inside the body and of course the body rests on the truck bolster. When All Nation sold these diesel kits, I suppose components were state of the art in their day.The platform that shipped with this kit was a material called Bakelite. With the invention of Bakelite in 1907, the polymer age was born. Leo Hendrick Baekeland was the inventor. The properties of this material were many however the use of Bakelite in the All Nation engine models served multiple purposes. First, it provide durable structure to the model and was resistant to oils, various chemicals, paint and solvents that one might find around a model. Second, it could with stand heat and third it provide an insulating barrier between the diesel body and the trucks to help facilitate electrical pickup from the rails. It seemed entirely plausible to make a replicate of this part on a 3D printer. And, in fact could actually improve upon the part in a number of ways. With the Bakelite, one had to fudge the holes and widen them out slightly to fit the screws into the metal sides on the body which were tapped. Therefore, the holes in this piece should allow a slight amount of adjustment, particularly when also mounting the motor brackets. Additionally, I added by integration a thin washer and allowed the bolster hole to be slightly less in diameter for the purpose of using a larger machine screw or for tapping it for the intended screw. This part measures 55mm wide by 52mm long by 2.5mm thick. Body side mounting holes measure approximately 4mm in diameter. You may recall some units came as dummies with no power. The platforms also accommodate kits that do have the power units and the tower drive mechanisms. One thing I was not keen about were the screws they shipped with the kit to mount the platform. The screws were 4-40 and 5.5mm in length. Classified as a straight slotted Pan head type, they kind of stood out on top of the Bakelite. With the 3D printed improvement, we can put a slight counter sink with a Chamfer on the edges of the screw hole. In that way they are less visible but will still securely mount the platform with flat head countersunk screw type. For contrast purposes the photos show 3 B units upside down on the bench, the one I need platforms for, the 2nd with the original Bakelite platforms and the 3rd with the new part mounted in the body with the original pan head screws from All Nation. The B units shown in these photos are not for sale. Printed with PETG filament sold as is straight off the Prusa Printer built plate, all sales final no returns. Made In The USA.