Hey, Themole,
I read that you got an MES 30 but am curious as to why you would want to run the wire for the probe through the door. I have an MES 30 and just stick it through the vent on top. You should be smoking with the vent wide open anyway so there is no problem with having the probe wire running down through the vent openings. Even if you get two or three probes they will run through the vent.
Hey all you new MES users out there, if you are going to smoke chicken or turkey in your smoker, I strongly suggest that you Spatchcock your chicken. What is "Spatchcock" you say? Glad you asked, what you do is, turn your chick over so the backbone is up. Take some good butcher type shears or a good sharp knife. Cut along one side of the backbone from tail to neck. Then turn it around and do the same thing to completely remove the backbone. If it is a chicken just turn it over and spread it apart, pressing on the breast until it lays flat. Now you are ready to season/rub your chicken on both sides and lay on the smoker rack skin side up. You'll find that your chicken will cook more evenly, not have all that fat gathering and sitting it the cavity to spill out when you remove it and will be perfectly smoked every time. Since turkeys are usually a bit larger I will usually cut them completely in half and lay each half on a separate rack. It too will then cook just like the chicken did, to perfection.
Every time I cook my birds this way, everyone comments on how good they taste and how tender and moist they are. Just make sure you use the thermometer in your bird so you don't over cook them.