The shp block just needs a finish hone job for 4.125 bore size( about .010)
We stock Callies crank and rods,Mahle pistons for 4.125 bore, 3.875 stroke , internal balance( 414")
Dart says 4.165 on the bore but we can go to 4.200 with the right felpro gasket ( 429")
Angle bolts on center caps, 2 piece rear seal, standard cam location

Bolt holes are blind

We have been sending these all over USA and also some to Germany, Austria, Australia, Domincan Republic

Jerry