Doesn't the gauze "straighten" the airflow over the MAF so it gets accurate readings ? In which case I'd leave it alone.
Remember when doing any comparison RR runs, ensure there are no other variables that could affect things; if there is a power increase from the intake, it's likely to be very small - and you often get small variances between RR runs anyway even when nothing has changed, so I'd suggest doing several runs first and averaging the results, and then doing several runs each time you've made a change, and averaging those too. Otherwise if you see say, a 2bhp peak increase just on one run, you won't know whether that's because of any changes you've made, or just typical variance you'd get anyway, in which case your results would be meaningless.