You can fill the blower depinding on what cover you have threw the stock fuel pump block of plate, a snout bolt hole, a pressure relief hole....
You want to add gear oil until it reaches the drive snout bolt hole in the 8 oclock position, pull the bolt and fill till it runs out, put the bolt back in and add a little bit more to be safe.
http://dyersblowers.com/nstallation_instructions.html