I am not seeing anyway to remove a LUN from a Zpool...
Am I missing something? or do i have to destroy the zpool and recreate it?
This isn't a best post to get fast answer. Please put some commands, system responses etc. .
Do you try using any command and get some error ? Generally I don't think you'd have to destroy zpool to remove a storage device from it.
According to the man page you can only remove hotspare and cache devices with the zpool remove command. You can also remove devices from a mirror using the zpool detach command, as long as it is not the last submirror.
So there is no way to shrink a zpool at this time. But there is a RFE (4852783) to implement this feature.