I managed to create Diamonds using levels and Enderchests

So here is what I did:

1.) crafted a Steel Anvil from Railcraft
2.) put a Enderchest in it
3.) named the Enderchest
4.) pulled it out

** I do now have a private Enderchest **

6.) remove the Diamond

** I do now have a normal Enderchest + 1 Diamond **

Repeat ... it worked every time

It basically exchanged 5 lvl against a Diamond

I am using the FTB Infinity Pack

That should not be possible, naming an Ender Chest in an anvil should not set the owner unless RailCraft is doing silly things, Anyway, This is on a 1.7.10 version that is considered Legacy at this point which means no support for it.