well there are some plugins that will do it but it works horribly. Basically you set the mouse axis x and y to a joysticks axis x and y using eithier a plugin for the emulator that supports this or a 3rd party program. Then you fiddle with the sensitivety until its just right. But since n64 games were never meant to work like this it works pretty bad.
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Q6600 Core 2 Quad || Soundblaster X-Fi Extreme HD || e-VGA 8800GTX || 4096mb 4-4-4-12-2T Dual-Channel RAM || MSI P6N Diamond || 2x 320GB Hardrive || 5.1 Speakers || Remote control || 8x USB 2.0 || DVD/CD ±RW Drive || 1x IEEE1394