Tapered Dog Teeth (Gearbox)- GT-6 Plus and TR-6
May, 1970
GT-6 Plus: Tapered Dog teeth replaced thinned dog teeth on 1st, 2nd, 3rd, and Top speed gears and sleeves at Gearbox # KC 19022.
NOTE: The following new details are not interchangeable with those which the supersede.
| QTY | NUMBER | DESCRIPTION |
| 1 | 152741 | Gear, 1st Speed |
| 1 | 518312 | Sleeve Assembly, Synchro and Operating 1st, 2nd, and reverse gears |
| 1 | 152743 | Gear, 2nd Speed |
| 1 | 153644 | Gear, 3rd Speed (35° Helix) |
| 1 | 518311 | Sleeve Assembly, synchro and operating 3rd and top gears |
| 1 | 216328 | Constants Pinion Shaft (35° Helix) |
| 1 | 213527 | Cluster Gear |
TR-6: At gearbox # CD 20282 a similar modification was carried out to the TR-6 gearbox.
NOTE: The following new details are not interechangeable with those which they supersede.
| QTY | NUMBER | DESCRIPTION |
| 1 | 216393 | Mainshaft |
| 1 | 216245 | Mainshaft (Overdrive only) |
| 1 | 152770 | Gear, 1st Speed |
| 1 | 152771 | Gear, 2nd Speed |
| 1 | 152772 | Gear, 3rd Speed |
| 1 | 216044 | Constant Pinion Shaft |
| 1 | 150989 | Needle Roller Bearing |
| 1 | 142434 | Constant Gear |