Hi Trickpony 4 if you happen to have a letter set of drill bits and a good drill press and vise for it you can very carfully use a X drill bit to open the hole up to where it needs to be. Warning !!!!!!! Since you are only removing a small amount of material from each side of the exsisting hole it will tend to grab and pull the drill thru all at once. That you want to stay away from as much as possible, If the drill press has a depth stop on it use it for say 1/8-1/4 inch at a time untill your thru.
Super 8 really has the best idea with the prop reamer,if your exsisting hole is straight you should be a fat city ,Caution again ,you will get tired of twisting the reamer in a hurry, please be sure to wear a glove at least on the hand doing the twisting. Ask me how I know this *L* Blister city.
Make sure to rebalance the prop afterwards, both tip to tip and the hub.
PS I'm working on your parts, but this darn walk in work comes first i'm afraid.