hi all , i have a harman wood/coal furnace and have been trying to get this thing dialed in!! tired of getting up every morning to start a new fire .... so tired.... so i've been doing a lot of reading on this site and others for solutions . added a baro. damper, still tweaking that but it has made a difference . and am always adjusting the draft controls to get the most out of it also read some where about adding firebricks on top of grates ... now in morning i actually have a bed of coals to work with..... anyways to my main reason for the post .... to be able to see the fire is the best way to determine how the stove is operating, i do have a temp. gauge on it to monitor what is going on but seeing is believing!! my warranty has expired ... so is it possible or a good idea to some how cut a window in the loading door??? get some high temp stove glass , gasket, fab some clamps and watch it burn !! i know this is getting long but really looking for some knowledge on how to get the most out of this unit..... anyone have any experience running this furnace ... secondary burn dials? any info or ideas .... greatly appreciated thanks in advance !