Thanks, elite-less, I appreciate the input. I was getting motivated to give it another shot tonight, but decided to make a few calls to see what the local shops would say. The local authorized BMW dealership said they don't have much luck trueing rims and wouldn't perform the work.
Really? With all of the BMW models past and present that have spoked wheels, they can't true a rim? Crazy.
So then I called a small local Triumph dealer. The gentleman there was very friendly and seemed very knowledgeable. He said he's been trueing rims for 30 years and could have it done in a day or two. I asked how much and he estimated $30 per wheel. SOLD!!!!
I'm dropping them off later today.