Having asked and delved just a little, I am posting this here now only in case anyone happens on this thread and needs info re the ignition amplifier and the 240 model.
The position and type of fixings that hold the heat sink to the wing on the 240 are such that the battery has to be removed to change the heat sink, unless one has a ball ended T25 torx driver/bit that can be used in a confined space. Mine is 1/4 drive on a stubby flex handled ratchet.
Otherwise one could for example be horribly vulnerable on a hard shoulder in the dark &c. with no lights on the car while fixing a replacement amp. EEK. Or waiting for a breakdown service patrol.
I understand the amp doesn't fail often but when it fails it tends to fail totally. So it is worth planning. (Obviously there will be exceptions to how the amp fails.)
Best plan for the 240 is to carry the spare amp mounted to a spare heat sink, and if reasonably possible also carry the "special tool" for the heat sink screws. Belt and braces with safety net. Did I mention be prepared?
Now this really is not 700/900 section stuff. I really will stay out of this matter in this section now.
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