Got some more updates, nothing that exciting but I like to share the progress anyway so I can keep a record for myself too of what I've done and when.
I got round to buying a decent heat gun and set to work on the sound deadening on the floor of the interior. Luckily I had a set of good scrapers to hand and me and the Mrs got stuck in.
After about 4-5 hours of intensive scraping we had cleared most of it off, some of the stuff came off in huge chunks thanks to a leak in the foot well which removed the adhesive from underneath and dried it out.
Here are some photos of before and after removal. It still needs tidying up but the majority of the sound deadening stuff was removed and in total it weighed 6kg's which is a substantial amount for a small car.