How to Copy world block IDs

I’m trying to copy some buildings from on world to another. Both are using the same version of Minecraft and forge and are using the same mods. The problem is that the block ids for the mod blocks are somehow auto assigned for each map. This means that I can copy and paste inside the same world but when I go to a different world the block ids are all messed up and the copy doesn’t work as intended. I found a forum post here

http://www.minecraftforge.net/forum/index.php?topic=24418.0

it seems that this person had the same problem and found a way to solve it but he didn’t give any particulates on how he did it. If someone could help me I would appreciate it.

I have tried both MCedit and World Edit both give the same result

Okay I figured it out thorough process of elimination I found it’s the FML entry in the NBT. So you just get NPTExplorer and copy the FLM to the level.dat for your new world.