engine swap?

Which trans Manual or Auto?

dude u have to change radiators,because u have trnny lines on tha auto. you have to get your driveshafts shortend and lengthend if 4x4. cuz the auto trans is shorter than a stick, well thats what i had to do from a manual trans to an auto. in my f-150

If you are taking out the engines and swapping them only you are good to go as long as both are carbed, they both should be if they are pre 86. If you are replacing the trannys too then you get into the radiator swap and the driveshafts. Remember that the 300 is a Loooooooong engine compared to the 302 and it is a pain getting it in there with the heads on much less the carb or intake. Take my advice here and pull off the intake at the least before putting it in.