In 1.0.182, It is not really possible ;
I used a Custom Class editor, But the fix is alredy implemented.
You can't have guns that you didn't unlocked, Nor 2 Primaries, Nor 2 Attachements without bling.
Pheraps I could try editing the Exe like HD did for implementing some cheats, If the fix is just lightly added – Will see if this is do-able –...
Be back on this subject soon, But no, You can't do this with just a trainer / Custom Class Editor, The game will just don't care.