First would be to compare and determine if this is a Feralite rod or, as it sounds to be, a sleeve ferruled model, and possibly a custom build. Using the Wiki Brian referenced, the search function here, and this thread in particular, you should be able to tell.
viewtopic.php?f=3&t=37987&hilit=yellow+Fenwicks#p124703Either way, it's a good heavy lineweight 'glass rod, but these are usually the least sought after by 'glass fans, whether collectors or anglers. The connection to development of Fenwick rods in particular, and fiberglass rods in general adds interest, but not all curios are valuable, especially if fairly common.
Sometimes a rod's ownership history adds to its value. IDK if you could count on that in this case.
Typically such a rod would sell for as little as $25 up to $150 or so. Searching sale prices on similar rods is the best way to get close. Whether that's worth the trouble as opposed to a quick sale at a modest price is up to you. Often it is easiest to list it on Ebay or other auction platform-- accurately described with good photographs--start at a low price, and take what you get. It takes a lot of research and marketing effort to get top dollar. That's why another good option is to find a reliable consignment seller. Their cut may seem like a lot, but it's often just the money you wouldn't make trying to sell it alone without a lot more time spent for a few more dollars.