I actually ended up bringing most everything I needed back as checked luggage each trip across the pond, which worked out okay as I was flying back and forth on at least a monthly basis.
Then they installed those x-ray machines to check every bag coming in (this is prior to 9/11) to make sure no one got away duty free. I learnt to buy a nice bag of coffee so I could declare it and go through the red channel with no x-ray as they assumed you were honest, having declared something
I got a whole CF Ducati exhaust system in that way 
On a more serious side, you need to find someone who is shipping via sea freight container, importing cars or car parts etc. and have them put it in the container. Either that or buddy up with a pilot who has some discretion as to what he can load in his plane.
Good luck,
Julian