These are the mods I have done to my Char-Griller Smokin' Pro with side fire box.
The first is the spaceship mod, which is just a foil insulation blanket rated for 500 degrees Fahrenheit.
This is a water tight electrical cable grommet I put in to run the digital therm probes. This way they're not being pinched by the lid. I found this mod in a thread posted on the Brethren.
This is a cheap reverse-flow mod I made using dryer vent hose. I attached it to the bottom of the smoke stack then bent it towards the fire box side of the cooker. I attached it to the side of the lid using a screw and a wing nut.
I lined the bottom and sides of the smoke chamber with HD foil for a cheap gasket. I then put in two red bricks on both the right and left sides to hold up my baffle/heat deflector and maybe add something for thermal mass.
Here is a pic of the baffle/heat deflector. I have to drill some holes in it when I get the time (lazy).
There is a 2 and 1/2 to 3 inch gap on the left side to allow heat to escape.
This is the dryer vent/ cheap reverse flow mod showing the vent at grate level. (sorry for the dark pic.)
This is the charcoal basket I made out of some expanded metal i had lying around. It's just bent into shape and held together with some metal wire.
Well, that's pretty much it. I thought I would post some pics for everyone to check out. Sorry for the blurriness of some of them (I have a crappy camera). Any suggestions, or questions, or even criticisms for that matter, are welcome.