While you wait for the neutering to take effect (and see if that successfully helps him to stop spraying), you might want to try doggie diapers on him.
...Always in my heart... Mocha....Nov. 13, 2002 - Dec. 6, 2013
.... Slave to Bengal Cats....Luna, Mystik, Simba, Komet, Meli,
Spark, and Star
.....and a collection of kittens at various times.