Ford 2003 Mustang Workshop Manual page 2826

6. Install the reverse idler gear on the shaft.
7. Install the reverse idler gear into the case.
8. Install a new seal on the reverse idler bolt, then install the bolt in the transmission case.
9. NOTE: If a new front input shaft bearing or front countershaft bearing was installed, install new
bearing cups.
Install the front input shaft bearing cup and the front countershaft bearing cup. Do not install the
shims at this time.
Install the transmission main case.