Not trying to get anything! I have an IMCR and might decide or be forced into an IR at some stage (see other thread!) but I am assuming the hours won't count for that unless they've formed part of a course of training, even if the requirements for the ground exams are made more sensible.
In which case your best best would be to do the FAA IR and then convert THAT to JAR via the 15 hr route depending on your total IMC time.
If you have enough hours, you can do the FAA IR within a week - one of my mates who now flies Airbuses did it in about 6 days from IMC rating - over a weekend, so it is possible.
Play your cards right and you can do it somewhere that teaches you JAR procedures and tolerances and so when you convert you can be sure to do it in minimums....
Just an idea
