Help inserting 512 kb header on SNES ROM.

I need a little help here. I'm trying to make a Tales of Phantasia SNES repro, but my usual header tool will not let me click the add header box for whatever reason. So it looks like HxD is my only option to do this manually. I tried inserting 512 bytes, by going to "edit" then "insert bytes" and typing 512 in the byte count box. There are a few more options I did not touch that I am not sure if I need to use. Like "dec" and "otc", then I left it as double 00 in the Hex-Values box. There also a "random bytes" box I left alone.

Honestly I am not even sure this is where I need to be going to do this. I keep getting a few more bytes then the dejap patch readme says I need to get. My rom is the size it needs to be before adding the header. So I think I have a good ROM.

Any help would be greatly appreciated.

http://ucon64.sourceforge.net/ < grab that

ucon64 --snes --swc yourgame.sfc output.swc

that should spit out a rom with a 512 byte header for you ^

\o_

Awesome, thanks man.