After 21 years of M-20 and 3:70 rear end and hipo 283 it may be time for a change--I have complete 3:08 sitting in the corner of garage--thinking about changing out the rear ends. Can't really go to overdrive just yet with early model 283 still in car. any opinions. Just a little tired of running 3500 rpm's and more on long trips. getting ready for Route 66 tour in a year or so. May just opt out for crate motor and 200r. thanks. Still liking shifting but running 3500 and above on the interstate for 3-400 miles at a time gets old.