will a 545RFE work with a 1974 318 la engine

no unfortunately they will not bolt up and the 545RFE uses control module and its part of the PCM which operates the engine as well cool idea though

but you could get a 46RH from a early-mid 90s dodge, which would be a 4speed auto with overdrive. you would just wire a toggle switch to turn overdrive on and off.

How many years have u been working with Chrysler transmission?

People answer these questions when they do not actually know the answer. That engine will bolt right up to the 545rfe. Top bolt will no longer be a thing though. The mounting surface on the 545rfe was beefed up from the bell housing of the 46rh. Thus the need for the extra bolts is gone. There are tons of old 60s-70s dodges that have been fitted with 545rfe transmissions using a 318 or 360 engine. They even have standalone transmission controller that can be installed. (you lose cruise control with this option) End of the day you need cam, crank, and throttle position sensors. You can use the crank and cam toner rings from the current engine and fabricate an attachment to the crank with a mounting surface to the block to hold the sensors. You can install a throttle position sensor on a carb to read the throttle position. This will make the transmission shift properly. Then its a matter of flashing out the o2 sensors, the coils, the injectors, and the egr valve. This will clear the mil from coming on. From there you just use the temp and oil sensors from the newer engine to make the gauges work with the older engine. Drop the fuel tank and remove the pump from inside the plastic housing and replace it with a pickup tube. From there its a matter of finding 12 volts from ignition and 12 volts from battery and you will have a running electronic transmission with a non electronic engine.