Managed to squeeze my time to go to the workshop today. Drained the MTFIII oil and replaced with 2 liters of Redline Lightweight Shockproof. A short drive back to the office and the 3rd gear crunch has gone completely. I can sleep soundly tonite and rev happily tomorrow.
Note to self not to use the nipis gear oil in the future.
The other thing I reckon today is that the Skunk2 control arm made the car's rear end firmer during cornering. Not much of body roll felt as compared to before and I do feel I can execute faster corner slicing without having to worry the tail to wobble. Thank you Skunk2 for an awesome product.