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WOW you brought back memories... These machines were the State of the ART back in mid '80s. They were the cause of the Y2K problem too. You should be able to go to a library and get a book about computer repair and find this data, if the book is at least fifteen years old. Best bet, go and surf the INTEL website for data sheets. By the way, these you mention are Math co-processors, there also was a 80286 before those and the 8088 before that... Thanks for the trip down memory lane.

You are talking about ancient history in computer terms. Which 386, the SX or the DX. Which clock speed - 17mhz up to 40 mhz? Note the 387 referred to the math co-processor, not the CPU itself. The 486 sent from 25mhz to 125 mhz and was also in both an SX and DX setup again with the 487 as the co-processor. You can google them for pin diagrams, suffice to say that they were not compatible and that companys like Evergreen made a 486 that would fit into a 386 slot plus a 586 (not a pentium) that would fit into a 486 slot.