Couple 46rh questions

moparmat2000 said
That I dont know. A 42RH should no counterweight on it because 318s and 3.9s are internally balanced. My 42RH out of a V6 had no counterweight on it. I am going to use a regular small block flex plate. You probably should use a neutral balance converter, get a flex plate for an externally balanced 360 like one from B&M. When I put an engine together I have my machinest internally balance the rotating assemblies to eliminate the special external balancing crap. Maybe somebody else can chime in as to weather or not the 99 360 converter will fit and work on a 42RH.

He cannot use a B&M flex plate because he is keeping the stock Magnum fuel injection.
The 5.9L engine will require the matching 5.9L balanced flex plate from the engine donor truck. The 42 and 46 torque converters will not physically interchange. Get the torque converter from the transmission donor truck if it is in good shape. Before assembly, make sure the 5.9L flex plate bolt holes line up with 42RH torque converter, as this part I don’t remember ever trying.