The first Struck Magnatracks used belts for fwd and rev , and used brakes to steer. The next generation, used a 4 speed peerless transmission and chains to drive, and brakes to steer. The latest generation of the Magnatracks uses hydraulics to drive and steer. In building something similar to the Magnatracks, you have to consider the HP of the motor, and how much pump can the motor run. Then you have to match up hydraulic wheel motors if you go that route. In considering the motors, you have to know how much weight the motor will have to push to drive, and if you push dirt with it, you will need a larger hydraulic motor. If using the Peerless 4 spd transmission, with sprockets where the wheels would normally bolt on, you then drive the tracks with heavy duty chain, going from say a sprocket of ten teeth to a sprocket of fifty teeth, which will turn the tracks. You can get tracks from many different manufactures, or make your own. As I said before, if I put my Magnatracks in low gear, it just slowly crawls along. I also have a dozer blade and a bucket for mine, and uses electric motors to raise and lower the bucket. My Magnatrack also has a 16 HP Wisconsin engine, with electric start.