Looking back at my notes from two years ago, hot compression numbers were:
8: 148
7: 156
6: 130
5: 148
4: 130
3: 145
2: 150
1: 154
The Volvo book claimed that numbers within 15% are acceptable, so I went with it. Luckily, I really only spent time and money refurbishing the 280 outdrive, which I'll definitely keep.
I've read bad things about the flat top pistons and non-hardened valve seats in this motor, plus the block water jacket was/is pretty corroded.
That said, I'm going to cut my losses and find a new or reman vortec 5.7 block.
