Well I may be boring but ....
Your page seems to be missing some facts with regard to the conversion.
1. A good idea is to make sure that you have been issued with the paper conversion from the FAA so that you are able to get Unrestricted FAA ratings added to it.
2. If you wish to have and unrestricted FAA instrument rating you must take the flight test and written exams. Rather than just the foreign pilots written exam for instrument rating. Which is fine for holiday flying but not for anything else.
3. If you do go this "Full" route you must have done a minimum of 3 hrs in last 60 days with a CFII and have a correctly filled in 8710 form. The unrestricted Single engine instrument rating will only be vaild on a single and if you do it in the Multi it will only be valid in a Multi.
Maybe missing some stuff but sure the nice gentlemen that concurred that I am boring can help you.
I am posting this from my experience of converting my licence and working as a CFII for 2 years.
Well hope that helps a wee bit
