Default [Q] I have a little doubt

I'm sorry if this is a stupid question, but I can't seem to find any specific answer in forums and guides.

I have a SGS GT-i9000t with CM10. I want to flash the stock rom on it, with odin v1.85 (to get the efs folder back, got problems with the imei), so I downloaded the rom from sammmobile. There's only one file, a .tar, I know you just have to put it on PDA, but my question is this:

do I need the pit file?

(I know in most cases is not necessary, but I'm coming from CM10 and I found some guides that said CM ****s up the partitions and whatnot)