Al,
That radiator with the XJ and IA tanks including the correct BO tag for a 396 3 row core ( used as you stated on L78 4-speed cars with 3.55 axle) should bring around $300- $400 in rebuildable shape. Pretty hard radiator to find if you need one. 454 cars had the same tanks on 3.31 cars (except A/C models) with 4-speed but carried a BQ coded tag. So a guy with an LS5 or LS6 can use this radiator with a tag change.
Tanks look pretty straight and if not cracked are where most of the value is.
Tony, you scored on that one!
Chris