Where can I deduct self-employed health insurnace for managing my own investment rental properties?

Rental income is typically considered to be passive income and you cannot deduct "self-employed" health insurance premiums from passive income. 

Even if the rental income is non-passive, there is still no line on Schedule E on which to deduct premiums paid for health insurance and no deduction is allowable.

If your rental properties rise to the level of a trade or business such that you report on Schedule C, then a deduction would be allowed. However, note that the foregoing would be applicable to real estate dealers or to rental property owners who provide significant services to their renters.