TREMEC's can be installed into 65-66 Mustangs but requires raising the tunnel 1.5" to make room for the taller main case. If the transmission tunnel is not raised the transmission driveline is greatly effected which will induce a vibration problem on de-acceleration.

1967 to 1973 Mustangs have a larger transmission tunnel, so no modifications are necessary.

Using the R model bell housing with a clutch cable kit will require using a diaphragm pressure plate found in late model Mustangs. 302 engines dated 1981 and earlier will need a 157 tooth 28oz imbalance flywheel, as do the 289 and 351 blocks, regardless of year.  302/5.0L engines will need a 157 tooth 50oz imbalance flywheel or otherwise know as a 5.0L flywheel.  We offer flywheels with fixed and removable counter weights depending on the need.  Removable weights are handy when there are plans to swap motors in the future that require different counter weights.

Since the TREMEC transmission mounting point is further back than stock 3-4 speeds, a TREMEC cross member is needed for early Mustangs.  The cross member is designed for use with the stock early transmission mount, so don't make the mistake and purchase a late model T-5 transmission mount as it will not work.

The TREMEC shifter has two threaded holes to mount almost any kind of shift lever desired.  We offer both stock like appearance shift lever, ball and boot and the Hurst classic style.  For those who like the Hurst look of the 60’s, there are several chrome levers to choose from. Hurst also offers five speed pattern shift balls in white and black or T-handles found in 69-73 Mustangs.

Be sure to save the automatic transmission speedometer cable, as it will be reused. You will, however, need to install a speedometer driven gear, which are available in a variety of tooth counts to match your differential gear and tire combinations. Installing the new speedometer driven gear is simple, it requires removing the c-clip and pulling the old gear off and sliding the new one on.

Automatics have a neutral safety switch, so that the car can only be started in park or neutral. Manual transmissions don't need the switch, which must be by-passed or the motor will not start. On early Mustangs the four-plug harness sticks out of the firewall above the master cylinder. Two of the wires control the reverse lights; the other two control the neutral safety switch. Splice two of these wires together and you've bypassed the neutral switch.

The starters from early 289-302 Fords with automatic transmissions work just fine. The starter from any '85-'95 Mustang 5.0, auto or manual, will work. When header clearance is an issue, 1992-95 5.0L Mustangs use a high-torque starter which will run about $130.