Sheet metal: 4-speed humps, floor pieces and IIRC full floors (Pass compartment). Also crank & door handles.
Interior: Some seat material, carpet, windlace & gaskets, maybe the SS-style side trim panels.
Trim: tail lamp lenses
Underhood: detailing items like decals and some seals, Maxie intake & exhaust manifolds and full exhaust.
Some items interchange '63-'65 plus less from '62. Note that the cowl, dash, roof & ft door window framing differs from the '62-'63 cars.
You'll get to know Kramer's, restorationspecialties.com, and Joe Suchy (major '64 guy).