Splitting roms for Cartridge Games

[diamondspringwater]

I was wondering how to split one of your adapted cartridge roms in two, so I could try to burn. I am trying to do Rich Dangerous I have removed the 4 0's from the start of the program. I am trying to use an Atari JR eprommer from Gossuin.
Thank you

[Petari]

Little late reply, but better later than never.
I have ROMsplit program:  http://atari.8bitchip.info/astopensw.php
At 2/3 of page. It is intended mostly for Atari ST TOS ROMs, but can serve for cartridge ROM split.
It may be that will need to correct image sizes after split (LO and HI) - can do it with some hex editor for instance - like HxD .