ok, are you in the boulder area?
I am in the south denver burbs.
The winds have been tough lately. Read the sticky on brisket, it's good info.
Get one or two wireless probe thermometers. Stick one in a kickstand of jalapeno or potatoe or whatever to keep the probe off the metal grates. The other one. not as necessary, goes in the meat. If you only have one thermometer, when you pull the meat in and foil it and drop it in the oven, if you are so inclined, the probe goes in the meat and you can pretty much rely on the oven temp to be what you set it to. I think, never checked actually.
I would suggest buying a fireproof water heater blanket and cutting and taping it with foil duct tape on the edges, then you can mount that onto the main chamber with small bolts, fender washers, and lock washers with nuts. Cut it a little shy on the side of the firebox, you dont need to tempt fate any more than you already do. Dont use machine screws, you will end up scratching the bejeezus out of yourself from the inside.
You can buy the rectangular pieces of expanded metal from the home depot. Get two of them, lay them in a cross fashion against each other and you can see how if you bend them up you can make a cube. I used a couple of smalll brackets with bolts and nuts to connect them together. Mark your lines and find a good edge to bend them against, hammer the bend down to get a nice edge.
Look to see if you can make a lower level inside the smoke chamber that you can fill with soapstone. I went over to the stone shop and picked up some odds and ends for free. Soapstone has very good thermal properties and will help you maintain an even temp as it wont get knocked down so easily. The bigger flat pieces go on the firebox side to get the heat to flow underneath and even out the whole hot side cold side deal.
Also, while you are at home depot you can get the rope oven seal stuff, I had to buy mine at Ace, but I think I saw it at home depot once I knew what it was. You can run that along the edge of the lid to seal the chamber better. This is great to do when the smoker is new, as it wont want to stick so well once there has been several delicious layers of smoke and grease film on it.
Consider buying a small burner to put in the bottom of the smoke chamber, I used one of those turkey fryer burner you can pick up for $30 or so. This will allow you to preheat the smoker quickly. Have to have the firebox door open or it wont stay lit. Dont try to run it at the same time as you are burning in the firebox, the firebox fire will eat all the oxygen and it wont stay lit. Potential bomb there! But with all the stone in the chamber you can preheat to 300 in about 25 minutes or so, and the soapstone will soak up all that heat and disspate it nicely. Lava rock will not do that, it will release the heat immediately. You turn off the burner and your heat will dissapear.
Measure the inside diameter of the smokestack and buy yourself a tall boy beer of matching size and drill out the bottom or some metal tube of some sort ( some folks use dryer vent tube) to drop the height of the smokestack down to a lower level so the heat doesnt rush out but you still have good flow. Somebody here wrote to get the flexible metal sheeting you can get to put on the bottom of oven and you can roll that up into a nice tube but I have never found it.
Almost all of these ideas came from other people on this website, I am no supergenius, but have found the wealth of knowledge here a regular treasure trove.