Yes. Most likely you will have to fix your fueling because now you are tuned to your current MAF.
Mm, sounds about right.
As I mentioned. I bought a new maf non-OEM. Scaling on that one was crazy.
My readings and actual load was through the roof. The car was running piggrich AFR 9 on WB02.
It was just to toast that shit and get back to my old one.
Btw: tried scaling MAF. It was no brainer.
Will not flash it in, but good to know how.