67 crate engine part numbers

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I'm trying to find the descriptions for these 67 crate engine  part numbers and where they may be found. These are written on the dealer invoices for mine and a friends car from the same dealer.    One is p/n 3910585 , the other is 3910587. I believe they are part numbers are for complete crate engines or short blocks but we have not found them in any manuals etc. The 585 is a 427 hydraulic lifter engine, the 587 is a 427 solid lifter engine. Thx for any help locating the descriptions for these two part numbers.