Velocity Stacks on a KZ550

Hey Folks,

So I recently picked up a 1980 KZ550A and have been working on it a good bit. I plan on changing the air intake and exhaust set up and one of the mods that I want to do is to put some velocity stacks on the carbs. I have been looking around on ebay and haven't really found any stacks that seem to be made for this bike. I read that these carbs have a 40mm diameter, so do I just need to pick up some 40mm diameter velocity stacks. Seems right to me, but I don't like returning things.......

Thanks,
Peter