Man that is a long crack!! Hope you can get it fixed. There's another crack repair process that uses overlapping threaded plugs, but that crack, going thru some of the reinforcement webs on the block, may be too big to dependably repair.
BTW, the "frost plugs" aren't really for that purpose. They're core plugs and used to hold the casting cores in place while the block is cast. It looks like the water (ice) level was below the core plug location, and they probably wouldn't have helped save it from cracking anyway.

I'd be nervous mounting that engine on the stand from the bellhousing. That puts a lot of weight forward of the vertical support. Please reconsider mounting it that way. eek


Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.