Tuning Take the liner out, when installing a high flow transfer port on FX barrel?

 

I wondered if it is nescesarry to take the liner out, before heating the brass peace, to install a high flow port?

I have seen on youtube videos on how to take the brass peace off, while using heat, but as far as I can recall, no one did mention if they took liner out.

My guess would be that if applying enought heat fast enough, the whole barrel assembly will not be that hot?