Yes, but what you have is four EPROMs with 8 [0:7] data pins each and a computer system with 32 [0:31] data pins total. Each chip fills one of the following ranges of data pins:
[0:7]
[8:15]
[16:23]
[24:31]
On the CPU and the ROM SIMM socket (if present, does the IIcx have one?) you can identify all 32 pins. I.e. pinout listing are available which will tell you whether a data pin on the CPU (or in the ROM socket) falls within the first, second, third or fourth range.
Trace that data pin from the CPU or ROM SIMM socket to the ROM chip sockets. If the pin for a ROM chip socket connects to a pin on the CPU that is numbered from 0 to 7 (or 1 to 8 depending on indexing) then that ROM chip socket is for the LL ROM chip. Simiilarly for a pin which connects to 24 to 31 in the CPU socket. The ROM chip socket with that pin must be for the HH ROM chip.
Or just get someone to send you a photo of a IIcx with ROMs properly installed, assuming that production ROMs have meaningful labels.