355 Valve Guides

Hi everyone. I have finally got around to doing a major on my 2.7 355. It's been sitting in the garage since I bought it over 2 years ago( other projects ahead in the que ). The 5-8 bank has had the valve guides redone in the U.K. While the engine is out I thought I might replace the other bank. There is a wealth of information out there, some of it conflicting. It looks to me that Nicks Forza Ferrari has the best uprated ones with the small flange. Would this be correct or does somebody who has been through this have a better option? Thanks in advance for your help and ideas......Regards Gary.