CAREFULL !
TOS eprom are oftenly direct soldered on the motherboard. You could swap the two eproms that hold the TOS of a machine from an other machine if you don't fear to burn the motherboard during this operation.
Everybody here forgot that you could simply use a TOS boot floppy disk, as long as floppy drive is asked for a new TOS before accessing EPROM TOS. Same for the cartridge port. So the floppy TOS will substitute the real EPROM TOS. It will be located in the RAM after it would have been loaded from the floppy.
To make a TOS holded floppy, you have to copy an image of the TOS you are interested in. Several programs exists to do so. They are the same as those used to make a TOS image for an ATARI emulator on PC. Then you have to make the floppy disk a boot disk.
I suppose some other programs will do so.
