OK, for all of you who have a 69-70 Attex maybe this post can help you out. (where the exhaust exits on the rear of the driver side, not between the two back wheels on the driver's side).

The Baker Hill was made with and without reverse. The Baker Hill also known as the "ATV Manufacturing Company Power Transmission" works with two disks, a caliper, and planetaries inside the disks on each side. Each side works independent of each other. It is almost like an inside out T-20 with disk brakes instead of band type brakes. There was the 5000, 6000, and 7000 series. The 5000 series had a smaller main shaft and was not as beefy as the 1 inch shaft on the 6000 and 7000. The 6000 and 7000 units were very popular for racers because of light weight and they are small so the race seat could sit low and back on the frame of the AATV for a lower center of gravity. Also, the early Attex "R" racing models had 15 tooth sprockets compared to 13 teeth that the regular transmissions had. This made the gear ratio a little higher and these Attex racing models could reach an advertised speed of over 42 mph......thats pretty fast for around 1969-1970. Hey Mike C and Don K, if I missed anything add it in if you could.