Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:5396745.
This is my take on a 4 link version of a Traxxas TRX-4. I got tired of 3 link so here it is. This setup can use mostly just the parts off of a stock trx-4. For the 4link, the 3rd link stays where it was on the skid plate and you use the Panhard bar as the 4th link. You'll have to get a 3x45mm screw for the on-axle servo mount, which also serves as the mounting point for the other end of the fourth link, in order for the steering to work with my design. You can also use longer rear-end links for a longer wheelbase. Just keep in mind the pinion angle can't be too steep in either direction, so all thread cut to whatever length you want also works for maximum adjustability. This Chassis uses the Stock TRX-4 TRANSMISSION. The stock battery tray works or any one of the low CG trays that people have come up with. The side panels also fit with minor trimming. I am using 110mm shocks but stock length shocks will work. The "motor plate" included is not necessary but it does help tie the chassis together in the front. I also have a scale 5.3 motor clone that I will post that screws to the plate.
For extra hardware, I ordered a small kit on Amazon or various other Traxxas hardware from the local hobby shop https://www.amazon.com/gp/product/B092JPDSXX/ref=ppx_yo_dt_b_asin_image_o04_s00?ie=UTF8&psc=1