HP-10 disassembly/reassembly

[[kby]]

Does anyone have a technique/order/trick for assembly the HP-10 calculator without bending a bunch of the famous board interconnect fingers? The HP-10 (aka the reserve power pack for the Sting series—no continuous memory) has three independent layers of interconnected boards. Two sets of fingers to connect the bottom to the middle; one set to connect the middle to the top (which is the keyboard). Unlike the HP-19c, the middle layer doesn’t connect to the top by a flex cable; the middle board is completely free. It’s difficult to see inside to align all of the pins while putting the keyboard (which is part of the top case) on, so it seems as though you only have a choice of first connecting the bottom two layers and then trying to connect the top by “feel” or connect the top and middle, then connecting that by “feel” to the bottom. In theory connecting the middle and bottom should be easier (2 sets of connectors) and then the top fit by feel, but the already poor interior visibility is worse this way. Thanks in advance…-kby