i had 2 face the same sort of thing when i got extractors put on my ute. I got extractors put on which toak the shop 3 days(which is poor for starters, then for some unknwon reason with out me even knowing they decided 2 change the welsh plugs. This was all finally done, so i went 2 pick it up and drive it home. U wouldnt beleive it, half way home the car overheated and warped the head(my temp gauge wasnt workin at the time). The stupid idiots forgot 2 put coolant in. So i toak it back and u guessed it, the wankers wouldnt have anythin 2 do with it. They wouldnt even serve me when i went in 2 the reception bit.
They refused 2 do anything about it and I had 2 get a new head put on myself with my money. Several months later i was told that i could have went 2 consumer affairs about it. Maybe thats what u should do 2!!!
Good luck mate, hate 2 hear storys like that!