Have you bedded any rifle before? A Howa isn't really any different other than the front action screw is in the recoil lug so you don't leave any clearance under it. You can find a video of bedding a Mauser I'm sure, it's the same principle.
"The action is designed to fit in a Remington 700 long action inletted stock that has been opened slightly to accept the larger diameter."
It's only .050 larger in diameter than a Remington 700 so wouldn't take much.
Looks like it would clean up without setting the barrel back if that's the concern? That would be dependent on the current chamber and your reamer though.