Hi Tony,
I'm not clear on why you feel you need a hot plate for removing the screen, but I'd be leery of using a cooktop, especially when a hair dryer will work suitably instead. The iFixit [product|IF145-198-4|iOpener|new_window=true] is pretty inexpensive and will do the job, as will a hot air gun if you have one. Here in the US, you can pick one up at Harbor Freight for about $17, but you do have to be a bit careful with it, as you can overheat an LCD or OLED display with them and ruin them that way.