Pete, I hope you recover from this very quickly! Your posts made me start thinking because I just tore/pulled a number of muscles in my lower back on Friday!! I have been out of it the entire weekend: no cars, work, repairs, no fun with the kids, nothing. Its Monday now and I can actually stand up reasonably straight. As for you, my friend, I can only imagine the pain and out of commission experience. I hope it all comes out in the end for you such that you fully recover.
Oh yeah, no more lifting engine blocks!!
Davy