Risk of squirters is a moot point, "problem" is there until block is changed out to a non drilled block, and I'm not really sure squirters are a definative cause of failures, fail mode on the 6.5 has not been proven to be caused on any one design flaw.
My personal experience leads me to believe it is a temperature related issue and if ignored those with squirters may fail in the region where the squirter was drilled, but the fact that one has squirters is not a certainty that it is predisposed to failure. Many 6.2s & 6.5s have had exact failure mechanism/location as the "bad squirter" blocked engines have had with non squirter drilled webbing
Myself I would not plug them, I'm not a big proponent on radical design changes without engineering data to back it up, if there are holes for squirters in the block, my major concern is "hot spot" at location that no longer has complete metal in it from drilling for squirters possibly needing flow thru the casting to cool the webbing as well as cooling piston skirts which could compromise the block even further than the squirters supposedly cause.
