Finished drilling and tapping the remaining NPT plugs in the left side of the case. The 1/8 inch NPT plug next to the oil pressure sender port rounded out after tightening a half turn beyond finger tight. Luckily there was enough of the plug still exposed to wrench it back out. I'll be ordering genuine Earl's plugs as replacements per Bob Hoover's recommendations - this set came from eBay and seemed soft.
Note: The eBay image is just for reference of price and part number and not intended as a recommendation of any particular vendor/supplier.