"Recover" to 2.02 withought jailbreak

[twist2b]

I got a recover file that is 2.02 (and i have 1.75 or w.e the original is)

Sooooooo, How do I "recover" it to 2.02 without jailbreaking or doing anything bad like that :O

Supposedly its possible

 

[therealmrbob]

shift click restore in iTunes and select the file and install it.