I just got this computer not long ago, and one of the first things I did was grab Minecraft and all my favorite mods (that have been updated). I grabbed the most recent build at the time, which was build 513. Today I decided to update all my mods and grabbed build 552. Now Minecraft is telling me that 21 blocks/items are now missing (mostly ore ingots and dusts). After checking up on the changelog to see what might have changed, I noticed that I had grabbed a 'developer build', which I'm assuming explains the issue I'm having.
How can I fix/adjust those block/item ids? I don't imagine this will require grabbing a copy of Eclipse and getting down and dirty with code (which I can do, if I have to).