Amazingly, under the treacle the engine was in excellent condition and the parts cleaned up very nicely. The current engine in my 96 was pretty sludgy too when I first got it, but I think this one's the worst I've come across so far.
my father got an XR4x4 as a sales car back in the 90's and my brother and I both wanted it until he took the engine apart - looked like it hadn't EVER had an oil change, the oil was like black jelly or rubber, he wasn't so lucky...