Quick questions about SNES PCBs

Hi guys,

Trying my hand at some SNES repros and thus far I've been successful with simple 8bit ones.

Question 1: If there is no SRAM on board, is there a difference between the HiROM and LoROM PCBs? Say I have a PCB from a LoROM game that has just the ROM and the CIC on it, can I put on a HiROM game?

Question 2: Are there programming differences between ROMs on the 74LS139 and MAD-1 PCBs? Say I match up a PCB for a game based on Hi/LoROM and SRAM, but the original game had a MAD-1 whereas my available PCB has a 139, will it work? I see a few examples where the same game has been released with either chip during different runs so I would think they're interchangeable.

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Well I seem to have answered my own question about HiROM/LoROM, I did some poking around on some PCBs and I see that the address pins are not exactly the same. However I'm quite sure I could put together a guide on how to use one on the other.. I'll get back to you all on that.. if anyone's reading this haha.

Question remains about the MAD-1/LS139 compatibility.