E-Series Chips

[Benoit Maag]

I have an HP-32E and an HP-38E.
Neither works and I want to try swapping chips to see if I can make one functional machine our of the two.
Both are the original non-solder type (left picture in http://www.hpmuseum.org/30comp.jpg) and have 1 large IC and 3 small ICs.

Does anyone know which ICs are common to both machines and which are specific to each machine?
Does anyone have the pin description for the LED display?

Thank you,

Benoit