340 Motor with 360 heads?

inside, under the valver covers "360" is stamped in between the pistons.
I am not positive but I would assume that meant they were for a 360?
ALso, the intake manifold isnt a perfect fit, the heads seem too large for it. Whomever owned this and worked on it before me seemed to have thrown everything together half@ssed. Lots of bolts, hand tightened, nothing in the steering column was connected, the dash was thrown in and not even hooked up, I can go on and on.