Hi Geoff,
If my memory is serving me correctly, the problem that you're experiencing is down to the air conditioning and the subsequent relocation of the radio etc. A friend of mine has the same air con unit in his 74 Rover, and the centre console is extremely difficult to remove. In order to remove it, it needs to move forward to clear the handbrake lever, but the relocation of the radio due to the air con makes that not possible.
I am sure that the console had either been modified in some way, making it shorter, or it had been broken at some point, probably in an attempt to remove it, as there are metal braces screwed into both sides adjacent to the front ashtray.
You may have to cut the console where the rear edge of the front ashtray would locate, then reattach and secure with metal brackets, screwing them into place once the new boot has been fitted and console is back in place.
Ron.