I'm by far no expert on 62's
The 318ci/5.2ltr or 360ci/5.9ltr
Magnum {not the LA SB 273-360 Chrysler}
is a truck engine {the 5.9ltr is externally balanced too}
no installs in cars from the factory
{if you keep the EFI get the computer & harness from the donor vehicle too}
but the block & overall height & width
are narrower than the old Poly style V8's
it should fit easily, I would think
there are parts available to convert it over to a carb too
the Magnum OE exhaust & heads flow relatively well too
not much bolt in stuff for the swap probably {?}
maybe try over @
http://www.1962to1965mopar.ornocar.com
you may need a special oil pan, since they only came in trucks
the rear sump style may work thou, came in Rams & Dakota's/Durango's
Schumacher Creative Services @
http://www.engine-swaps.com/
"probably" will have the motor mounts, maybe other stuff too
good luck