'89 360 LA valve spring/cam confusion

Got that covered! The 89-91 motors (which mine is) use the pre magnum heads (Magnum dimensions, LA intake bolt pattern) so have the Magnum rockers & oil through pushrods already.
The roller cammed LA engine I just rebuilt was all LA and had nothing Magnum on it. LA heads, rocker gear and solid pushrods that were not oil through type. Not sure how yours does if you have a pre-magnum, LA engine. Can you post pictures of it. I'm curious to see.