Just got and 85 442 trans code MXO is this a lock up trans? The car has 63,478 mile on it now all original I'm planing on replace the 307 for a 403 I build. If this trans is a lock up has anyone ever made a manual switch for the lock up as i wont be using the carb or distributor the ecm uses feedback from them to lock up the converter. The trans works great with the 307 hits a hard second when your on the gas hard.