When GM and Fiat were kissing cousins, there were two Alfa dealerships in Mexico - in Monterrey and Mexico City. Once the two broke their ties, the dealerships were closed. This left many new Alfa's running around Mexico with little support. I have seen a 166 and 156 in Texas with Mexican plates. Because of NAFTA, you can legally cross the border with for several months at a time without problems.
I have received several calls in the last year from late model 156,166, and 147 owners asking if we worked on these models. I told them we would try, but since these models were never brought into the US, technical and parts availability are hard to come by.
We had a customer who wanted a 156GTA. We spoke with a big ICI here in Houston. After much research and many phone calls overseas, a late model Alfa would be every expensive if not impossible to legally convert for acceptance here in the US by the EPA and DOT. The biggest problem was the glass, and lights. Major changes would be required to meet the crash standards. The shop guesstimated a cost of around $50K if possible to get the lights and glass to meet the US standards. The customer balked when you figure the cost of a new 156GTA, shipping costs, and conversion costs.
Hopefully in 2009 the 159 will be available in a Q4 configuration. I will be in line to get one of those.