I just finished rewiring a MES 40 with a PID. I looked at every pre wired controller I could find on Amazon, like the one you linked, and none were high enough amps and went to high enough temps. I went with the MYPIN TA4 http://www.amazon.com/Digital-Display-Temperature-Controller-thermocouple/dp/B00BVWYI8G?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00, I think this is the link to a pdf of English manual. http://www.smokingmeatforums.com/attachments/864 note that you need the one with the last 3 letters SNR - which means it will send a signal to an SSR. It comes with a k thermocouple
I got this SSR and heat sink http://www.amazon.com/uxcell-SSR-25-3-32V-24-380V-Solid/dp/B0087ZTN08?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s01, which comes with the screws, but you will also want some paste to apply between the heat sink and the SSR http://www.amazon.com/StarTech-com-Thermal-Compound-Heatsink-SILVGREASE1/dp/B00006B8DX?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s01
I also bought a power switch,http://www.amazon.com/TOOGOO-Light-Rocker-Switch-28x22mm/dp/B00E34BCCE?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s01 and a fuse holder http://www.amazon.com/Ancor-607010-Marine-Electrical-Holder/dp/B000NI5ELO?ie=UTF8&psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00 ( I picked up the fuses from Home Depot ). I made a box for the PID out of wood, and cut up a heavy duty extension cord to use as the plug and outlet, so the MES plugs into the female outlet, and the male end of the extension cord plugs into the wall. All in all, it was not that hard, though I did not realize that the SSR is powered by DC, so you have to get the polarity from the PID to the SSR right to make it work.
The big LED is because I couldn't a smaller one that was cheaper.
I wanted to take the PID off the MES when I wasn't using it, so I took apart the original control box and reused that quick disconnect connector to wire to the PID and the wired the thermocouple to the other end of the quick disconnect, and thread it through the hole where the wire went through to get to the original controller. I attached a photo, not sure how clear it is.
If you go this route, I suggest you rewire the MES so the power goes through the thermal bypass switch, and not directly to the heating element, that way, if something goes wrong, it will shut off, not overheat. If you have any questions, I had a million till I did searching on this site, let me know.
Edited by barryvabeach - 5/5/16 at 6:17pm