Hi Peacock72,
Others here may give you a more authoritive answer, but meantime ? no, the serial number will only give you the date of the guitar, not the model number.
Very early models often have the model number stamped into the wood at the end of the fretboard (mostly on Reborn & Reborn Old, c.1979-81). Otherwise, most Love Rocks have the model number written inside the pickup cavity; not very convenient of course.
Apart from that, you just have to guess from the quality of finish & fittings (if original). Eg., top models like LS150 & above should have flamed 2-piece top, 1-piece back, bound edges to fretboard, and more expensive pups etc. Whereas base models like LS50 may have 3-piece unmatched plain-grain top & standard Gotoh pups. Intermediate models, are.....eh....intermediate. Hope that helps :-? .
Ian.
