Actiualy from what I see only the case, backplate are useble-the rest will go to the trashcan. All steel parts yuo better dump it and don't even think to polish them-all parts inititaly ground and now rusty, you can make them shiny, but all tolerances will be lost.
To get new cranck, new P/S set, new bearings-it will be cheaper then new engine, but I am not sure if it is worse it.
BTW, there is some acid which will clean all rust out, don't remmeber the name of it, but will go to the lab now and later will give you the name.
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