You have to change that and specify the offset in the python script by doing ./insert.py --offset 0x800000.
Kleenexfeu did some subset of what I did in ASM, but he is insane. I prefer doing C because it's just easier to work with. I realise my method is probably a bit more difficult to insert, but I plan to make it better sometime in the future. The scripts really help me work because once they're set up I don't have to bother reinserting everything, I just hit a button on my keyboard to rerun the compile and insert scripts. Porting kleenexfeu's stuff back to FR is probably going to be a nightmare, you'd have to find the equivalent place in FR for each of his routines, and then change all the addresses to their FireRed equivalents. Also, I don't really see the point in redoing the work again. It would be easier just to write some C code that works for both games.