Okay, Wayman, this looks a lot better! I pored over the Hewes Performance videos to find the best image of your "hole". At http://www.4wdmechan...d-Bearings.html, check around 4:04 minutes, with the HD mode in full-screen view...You'll see a "hole". This is a casting design, likely to drain pooled oil from the lifter area and provide more timing chain lubrication in the process.
Sounds like you're doing a detailed rebuild and observed the rough casting edges at the hole. Unfortunately, casting flash is common on cast iron, mass produced engine blocks. I always go over the block and assess what poses a threat of sloughing off fragments—the risk of a piece of casting migrating into the crankcase or between moving parts.
The rationale "well it stayed put this long" doesn't work for me, and apparently, you're discriminating, too. If in doubt, take a die-grinder with carbide burr tool and smooth out the rough edges to the point that the casting looks stable, nothing excessive, just enough to remove the threat of sloughing. Always remove debris thoroughly, including any fine iron powder from the grinding process. This is abrasive stuff!
Make sense? Does this confirm what you're looking at? If so, don't attempt the use of J-B Weld—if the patch doesn't set well or is affected by oil over time, J-B Weld or similar materials could slough and end up in the oil pan. The threat here is plugging up the oil pump pickup screen, although it would take a lot of J-B Weld fragments to create a significant problem.
As a footnote, my remarks are not intended to detract from the value of J-B Weld...I can think of many occasions where the right J-B Weld product has been a tremendous asset: as an emergency trail aid or inexpensive way to save an expensive, damaged part—like a non-stressed motorcycle side cover with a chip or crack.
Trust this helps, Wayman...