Td5 Exhaust rear section - how to remove

Since I've not done any motor mechanics since I was at college, please indulge me. How on earth do I undo the rear section of the exhaust on my disco 2 td5? I've seen the kwik-fitters and their oxyacetelene torches in the past heating and cutting rusted bolts. Do I need to cut the nuts off? Ouch! Serious suggestions appreciated.

Angle grinders are useful tools on landies...

Its pretty straighforward, but no need for a gas axe. Spray the bolts with penatrating oil, give it a while then a spanner on each end of the nut and away you go. If the oil hasnt helped then apply heat. We have a tool for the job that is like a super bunsen burner, but a blowtorch will do. Heat the head of the nut until it just glows and attack with spanners again. If all else fails then grind them off. Keep away from the gas axe, it will eat everything it touches. Mask fuel lines etc and anything nearby that can be damaged by heat/fire. Good luck.

If it's the original system cut the pipe, you won't have "nuts" as it's a one piece system.

Cheers. I have sprayed on penetrating oil but perhaps was not patient enough before attacking it. Tried a blowtorch but obviously didn't get it hot enough. Perhaps the oil will have penetrated a bit better by tomorrow. I have the grinder on standby!