IR receive from lg tv remote send to yamaha amp

So i am currently running a lgb17 oled in my lounge room and i run an rx-v681 amplifier in my cupboard at the other end of the house. i run my sound to receiver via optical. so the volume up and down on lg remote does not control sound on amplifier. My hdmi runs thru extenders and is not able to pass the cec thru. What i would like to do is using arduino uno i would like to receive lg remote signals for volume up and down . and re send them to control the volume on the amplifier.
I have done some research but i have not much of an idea of what im looking at. So basically what i want to do is

Receive lg volume+ and send Yamaha volume +
Receive lg volume- and send Yamaha volume -

What i know is the codes for each
lg volume + 20df807f
lg volume - 20df00ff
yamaha volume + 5ea158a7
yamaha volume - 5ea15827

Any help would be greatly appreciated. Thanks