Without knowing what brand fireplace you have, can only relate to the one in our HC.
There is a removable front 'picture frame' that slides down over some hooks, for no better description. Those hooks hold that frame fairly tightly against the fireplace body itself but as we found, some of the North American shovel ready roads are rough enogh to dislodge that frame, making the heater tough to start/stop and adjust.
As far as installation - after removing that frame, 4 screws hold it in place. Pull them and the fireplace comes right out. You can then just unplug it from a common 120VAC receptacle. If you do pull it out, don't be surprised to see some construction debris behind the heater.
Oh and welcome to the site and be sure to fill in your sig line with what model, etc 5er you have
Traveling with my DW Susan, a couple poodlepups and our 2014 Montana High Country 343RL, being towed by a 6.7 2011 F250 CCLB using a B&W hitch and OEM puck system