It may not seem like it, but removing / replacing an IC and seeing no change is actually good in one respect - it means you've successfully carried out the work without introducing any further faults.
Sorry it didn't turn out to be UE7, as Tim said the 74LS244 buffers (UE7) have a bad reputation for failure and as Tony said, 2114 RAMs (UF7) are basically just regarded as electronic fuses...
...So it'll probably turn out to be UF9 after all!
How are you taking the ICs out, in bits or in one piece?