Port Matching / Removing imperfections in intake / exhaust manifolds

Hi All,
I just received the ATS throttle body inlet, and about to do some spanner work on the car.  
Whilst some parts are accessible, I am considering to port match removing/smoothing out any imperfections, on the intake / exhaust manifolds.
I am not in the financial position to go to aftermarket intake manifolds etc ($1,000s), so doing what I can with what I have.
The plan is polishing and removing imperfections, not reshaping.
Has anyone done this, any tips, any thoughts,
Cheers