Best off removing the hole assembly, you will find the bottom arms easy enough to remove and the top arms via the upper mount. You will need heat & a lot of force to remove that bolt, even with the upper arm off the car took some major heat and hammering to remove the pinch bolt..
Also the hub bolt is something like 200nm & half a turn took a big breaker bar to do the 1/2 turn (That is on the 3.0TDi engine).
You will not get enough heat in to the upright not to damage the top arms, it's not just the rubbers that you will affect with the heat you will boil off the grease in the top arms as well as they were never designed to take the temperature that you need to apply to get that bolt out. The only option you have is to try and press that bolt out, but my 10 ton press without heat would not budge the pinch bolt.