Peugeots, like most of the big-name manufacturers active during the bike boom, made a wide range of bikes, from low-quality boat anchors to top-of-the-line racers and touring bikes. The uo-8 was their popular entry-level road bike; it weighed a ton and was the object of much snobbery, but uo-8's are loved to this day for their steadfast reliability and bulletproof nature. Different variations of each model existed, and the various numbers/letters will tell the astute Peugeot fanatic whether the bike was originally outfitted with fenders, dynamos, etc... By now, many have lost some accessories, and/or gained others, but it's cool to know how it was originally equipped.
French-made Peugeots-- basically, everything pre-1980 and many/most early-80s models, were all made to Froggish standards, and are not worthy as donor parts if they have anything threaded on them. In the 80s, Peugeot started offering bikes made in Japan and Canada; these will have more standard bits hung on them, and make better donor bikes.
Px-series bikes, and other higher end models, have some collector value. All of them have value to francophiles willing/eager to deal with obsolete French build standards. Whatever; you gotta make up your own mind about that, but unless you want to deal with French headparts in a non-french headtube, that fork won't be much good to you--unless it's Japanese- or Canadian-made. Here's a source for more/better info than what I can offer here:
http://retropeugeot.com/