simple answer is: NO
You need only valid IR-ME to start the typerating, which is the entry requirement for the typerating/IR.
At the end, you will attend the typerating licence skill test for specific type and type-based instrument rating. So you will be again holder of the ME-IR.
According to the PART-FCL, instrument rating is allways related to the specific type ie B737, or class - ie MEP(land).
Should you need any help, contact me, I am EASA examiner.