If you don't already have it, get the Decca (London) recording of him in the William Tell. One can debate the Muti recording on Philips being a better musical performance, but on this Luciano's voice is glorious.
http://www.amazon.com/Rossini-Guglielmo-William-Pavarotti-Ghiaurov/dp/B0000041RE/ref=sr_1_1/102-7569851-6597728?ie=UTF8&s=music&qid=1189120714&sr=1-1
http://www.amazon.com/Rossini-Guglielmo-William-Pavarotti-Ghiaurov/dp/B0000041RE/ref=sr_1_1/102-7569851-6597728?ie=UTF8&s=music&qid=1189120714&sr=1-1