I have been carefully modifying the Omron MY2-02 relays successfully for years now.
I first saw it on Chrismarantz's Faultlineaudio site which is no longer active.
I just did one yesterday for a client's 240 amp.
It's delicate work but beats some of the High School Science Fair jobs I've seen on eBay where they silicone it on sideways and add a bunch of wires or some Mickey Mouse outboard circuit board.
I'll attach a few pics
Here's the relay after modifying.
You have to reverse the coil wires and the movable armature wires.
I carefully unsolder the white wires and move them out of the way temporarily.
The older relays in the Faultline Audio tutorial had flexible wires connecting the coil wires to the pins making it much easier but Omron changed to a solid coil to pin connection about 4 or 5 years ago so now you have to carefully cut the metal strap out between the coil wire stud and the pin.
Once this is done I solder a insulated jumper wire from the coil wire stud over to the middle pin which in the 1200/240/250/250M relay circuit board is the coil feed.
Then I solder the white armature wire to the back pin and repeat on the opposite side of the relay.
Put the cover back on and you have a brand new unobtainable relay!
To make it fit the board properly you have to slightly skew the pin holes so the smaller footprint relay will fit the existing holes.
The only difficult part is taking your time and being very careful not to touch anything else with your soldering iron while working in the close confines of the relay.
The finished look is well worth it!
Bob