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In permanent magnet (PM) machine drives, the initial position is typically estimated based on the machine inductance variation and the flux saturation. The saliency-based method using the voltage signal injection has demonstrated the reliable position estimation for high salient PM machines at initial state. However considering the saliency-based drive on low salient machines, several implementation issues appear due to the low signal-to-noise ratio of position dependent signals. This paper addresses the implementation issues on saliency-based initial position estimation. It is shown that conventional saliency-based estimation methods might not be able to obtain the correct rotor position on low salient machines due to secondary saliency harmonics. A two-step estimation process is proposed to improve the initial position estimation accuracy on low salient PM machines. Two PM machines with different saliency ratios are tested for the experimental evaluation.