I thought I was going to be assembling my L98 bottom-end this evening, but now I'm concerned.
When measuring the ID on the mains with the caps installed and torqued (no bearings), I got the following readings:

Front of #1 main measured vertically= 2.6412"
Rear of #1 main measured vertically= 2.6419"
Front of #1 main measured horiz= 2.6437"
Rear of #1 main measured horiz= 2.6428"

Mains 2-4 all measurements between 2.6416" and 2.6421"

Front of #5 main measured vertically= 2.6420"
Rear of #5 main measured vertically= 2.6425"
Front of #5 main measured horiz= 2.6409"
Rear of #5 main measured horiz= 2.6408"

(horiz measurements were made abt 1/4" above and below the parting surfaces)

I can't find a spec for this specific measurement.

I've read that a little wider horizontally is normal (and desireable) to prevent the bearing ends from gouging the crank, but don't know by how much.

What really concerns me is #5 main is narrower horizontally by .0017" .. Seems like a lot.

Should I install the bearings and re-measure?

Does the #5 main bearing get thinner near the ends?

Does block require a line boring?

 

i've built two or three engines and have never worried about the size of the hole, except on 4 cylinder pinto engines because they have differant size bores so you need to know to buy the bearings. only thing i've ever measured is the ID with the 2 bearing shells installed, that's what really matters, and i have checked the bearing bores for alignment with a straight edge. i don't recall ever seeing a spec on the bore size so i wouldn't worry too much about it.