Sorry for being a newbie with this program, but how would I input this in the Dementium 2 (U) rom?

Rom:      Dementium_II_USA_CRACK_PROPER_NDS-XPA
Hex edit: 00004800: ACB504EA→01C3A0E3
Clean:    Dementium_II_USA_PROPER_NDS-iND

I don't really know if the names of the rom matter, but I put them here anyways, just to be on the safe side.
I've removed the arrow and something popped up, which I couldn't understand. I tried it and nothing had changed.
Please help

Thanks in advance.