MM3/MultiMode3 hex dumps (Hex\MultiMode3 12C508X\) will work with pretty much every PS1 except for the PAL PSOne slim models, as it has the extra detection (using some detection for custom boot logos? Use OneChip instead for these consoles).
The MM3 hex dumps here work on 12C508, 12C508a, 12C509, 12C509a PIC chips.
Although a rewritable version of the PIC like the 12F508, should in theory also be compatible but is not tested! - Tested 28/02/2020, doesn't work and boots every CD as an Audio CD
A port of the original MM3 was done in 2012 for the 12F629 PIC chip (same PIC used for the WiiFree).
Check (Hex\MultiMode3 12F629\) for these.
ONEChip (Hex\Onechip 12C508A\) is designed exclusively for PAL PSOne slim models.
However the onechip is documented to only work on 12C508a and not 12C509/12C509a/12C508 PIC chips!
A forum thread suggests a 12F509 may be compatible also and has been tested by another member. ONECHIP compatibility unknown however. I have not personally tested.
http://www.psxdev.net/forum/viewtopic.php?t=1541
Both the ONEChip and MM3 chips are stealth modchips.
HQ Modding diagrams for the MM3 are in the \HQMM3-Diagrams\ directory. HQ Modding diagrams for the OneChip are in the \HQOneChip-Diagrams\ directory. Classic 2000s low quality MM3/OneChip diagrams and PAL60 colour mod diagrams are in the \2000s-Diagrams\ directory.
PAL60 Colour Mod is only required if your TV doesn't support NTSC 4.43 (as modded PS1 PAL consoles don't use a pure NTSC 3.58 signal).
In my experience, every CRT TV that I've used in Australia has supported either mode. However funnily enough quite a lot of modern LCD TV's that I've used don't support the PAL60 mod and support the NTSC 4.43 mode anyway. So doing the mod actually breaks colour from working (often looks sepia, or doesn't sync at all).
SCPH-550X and below may require an external crystal for colour in NTSC games however. Check \2000s-Diagrams\NTSC 3.58 PAL 4.43 Color Mod 100X-550X.PNG for more details.
Software for the K150 PIP Programmer board are in \Hex\K150\ I recommend watching MrMario2011's guide on programming the PIC chips.
Enjoy and good luck! ~Kippykip