As one who repaired a few logic clips back in the day it looks like the DIY approach above missed something HP did, which was to interconnect the Vcc and local ground busses across both sides of the logic clip. IIRC HP used differently marked 20-pin IC packages in their logic clip so that just bending the end pins (and soldering them) across sides provided that interconnection. The ICs were mounted solid, only the contact wires flexed.??
