The 420a is a Chrysler motor. Similiar to the 420a in a Neon but not quite. Intake and Exhaust face the opposite direction on the head. Its prefered and known more as a Chrylser engine not Dodge.

No 4g63/4g63t parts will work on the 420a motor. Like I stated in the other post the only thing you will be able to use is a 1g BOV and a 1g/2g sidemount intercooler if you plan on piecing a kit together other then that the parts from a 4g63/4g63t will not work on a 420a and vise versa.