MEAI Requirements
 

I've been out of the flying game for over a decade and getting back into it. Just weighing up whether I just do the proficiency check flight for my SEA FIR Gr 2, or just dive straight into doing a MEAI instead.
CASR Table 61.1235, item 15 (Multi-engine aeroplane class rating instructor training endorsement) says the requirement is "CPL ATPL with aeroplane category rating, Grade 1 training endorsement (aeroplane) or type rating endorsement for a type of multi-engine aeroplane".
I have an ATPL and about 500 multi hours, so no problems on that front, but item 15 of the table seems to say I first need to upgrade my SEA FIR Gr 2 to SEA FIR Gr 1, and only then can I do the MEAI.
However, when I look at item 2 and 3 in the same table, column 2 suggests that a Grade 2 can add the MEAI to their rating, that is a grade 3 endorsed FIR is explicitly restricted to 'Conduct flight training for a single-engine aircraft class rating', but for a Grade 2 "Conduct flight training for an aircraft class rating".
It appears unclear to me which way around I should approach this.

The MEAI as you describe is the training endorsement for Multi-engine aeroplane class rating instructor. Ie. An experienced multi engine instructor teaching a newly fledged instructor in multi engine training practices.

If you are seeking what in the old terms was a 'Multi engine training approval' you will need to complete training for a CLR MEA (Class Rating Multi Engine Aeroplane) see CASR 61.1235 item 6.

Hi Dynamic, you're correct, I was looking at the wrong item, and it is in fact item 6 I should have been looking at. So it's only 50 hours of multi aeronautical experience required, and I exceed that. So I think I am better off just diving straight into the upgrade rather than going through an instructor proficiency check on singles and then an upgrade.