How I check EFI version on Imac 27"?

[zinger123]

Hello.
1.How to check the EFI version?
2. How to install EFI 1.6 to Imac 27" with 4850 (late 2009) on LION 10.7
I always get error massage - "this version cannot install with this system"!

 

[zinger123]

thanx very much

http://support.apple.com/kb/HT1237?viewlocale=en_US