I think you're heading for problems. Particularly depending on the type of puffer and the type of cichlids... Not all puffers are the same, nor are all cichlids... even if they're all from the same lake.
The puffers need brackish water as young fish, and potentially full on salt water by adulthood. The cichlids could handle some salt, but not the type of tank you'd need for the puffers.
I think most will tell you that puffers belong in a species tank. So the only thing in the tank should be the puffers.
There are many other choices out there that are a lot more compatible.
Joe