So I got everything I needed today to make the 10G Home Depot Mash Tun. I want to be able to have a thermometer in it so I can read the temp without taking the lid off. I want to just use the thermometer I already own and be able to take it out to use it for other stuff. The digital thermometer I have is only about 5 inches long. So My plan was to use like 1.5ft of copper tubing through the lid to reach down into the grain bed. My question is this; Will this give me an accurate reading of the temp since my actual thermometer probe is only 5 inches into the thermowell?