Can the .signed file found inside a radio .bar file be used for creating a radio autoloader?

I want to create an autoloader to install the 10.3.2.2640 radio on a friend's Z3. I am unable to find a .signed radio file. I opened the radio bar file as an archive and found a .signed file inside. Can I use this .signed file to create an autoloader?

I cannot use sachesi to push the bar file to the phone because I'll have to physically be there with the Z3 to do that and I do not want to do that. An autoloader is simple to use and I can just upload it so the friend can do it without me. The friend is not tech-savvy enough to use sachesi.

Please help.

Yes.

Take the .signed out of the .bar and make a radio-only autoloader with it.