As well as this many hours of this and this many hours of that, you should also think along the lines of building relevant instructional experience:
1. As a restricted FI you need to show you can teach and judge solo readiness
2. As a FI you need to show you can get people through the PPL to a good standard
3. Once you can teach applied instrument you need to show you can get people through the IMC test to a good standard
4. Next comes CPL instruction, proving you can teach to a standard acceptable to a CAA examiner
5. Finally you arrive at MEP & ME/IR instruction, and again you need to get people through the test with a CAA examiner.
Instruct for a couple of yours and you can achieve this. The hours required should pretty much fall into place over this time period.