Should be a doable swap, I would not see a problem with this as SS/LS was mostly engine and trim differences.
the ss nose will line up on the ls, but you need to get the lower front fender trim from the ss as the ss is a different shape the closer it gets to the bottom. the ls lights will work, but some modifications need to be done to the brackets to get them to fit into the ss nose. the hood is the same, as well as the rest of the area surrounding the nose. However, the bumper support may be different due to the different shape of the nose. That is something youre gonna want to look into as the ss nose is a softer one as compared to the ls nose and may cause the paint to crack if it is not properly backed.
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