bad module in block 8 didn't show on OBD?

You start counting block 1 from the opposite end of where the electronics/relays are located. I think you're counting on the wrong end. That's why you have block 8 instead of block 7

 

Module screws on the bottom are good at 48 inch pounds. (3 ft-lb)
The 4 long bolts that clamp the modules together just need to be tight, as the tubes will limit the compression to the proper distance. If you need an exact value, just look up recommended torque value for the thread size. M8 x 1.25 calls for about 19 ft-lb.

Let me back up a minute, 19ftlb is for the higher grades. Most likely the bolts used are junk, so stick with about 7 ft-lb. I'll have to dig one up and see what grade it is.

OK, my eyes are blurry now trying to find numbers for the markings. I looked at a few. A Gen 2 has 4 lines on the head (3 at top, one at bottom, looks like a palm tree) the other, a 2013, has 2 dots on the head. Can't really find anything for either one, so here's my technical analysis:

I know my 18v Ryobi impact driver usually cannot loosen these bolts when initially disassembling a battery, but my Dewalt 20vMax impact driver has no problem. That alone tells me they torque the **** out of them at the factory, so go ahead and make em as tight as you want.The important thing is that you have them tight up against the tubes.