Yes, I think you will need to take the test before applying for ILR. I should also say that I think you have misunderstood the requirements for becoming a British citizen...
If you are intending to apply after THREE years residence (as the spouse of a British citizen) you will need to take the test, because you will be applying for naturalisation as a BC, and all naturalisation applicants need to take the test.
Registration applicants don't need to take the test, but they can apply only after five years residence. (Registration, so far as adults are concerned, is a simplified form of application, available only to people who have a category of British nationality, other then full British citizenship - eg BNO, British subject, BOC, British Protected person...)
paul