"This is a single wire alt. am I able to totally eliminate he voltage Regulator?" assuming your alternator has internal regulator you would definitely get rid of the generator regulator.
Is your tractor presently positive or negative ground? With alternator it likely must be negative ground.
Connect your BAT connection from old regulator (other end goes to ammeter) to the output of alternator. Would be good to replace this wire and one from other side of ammeter to battery connection at starter solenoid/switch with 10 gauge wire.
If your regulator has an L terminal this feeds power to the switch. You can either connect the L wire to output of alternator, or run a wire from switch to alternator side of amp meter
With switch/lights on, engine not running, does ammeter swing positive or negative. If negative leave it, if positive reverse ammeter connections.
With negative ground the negative - post on coil goes to side of distributor. Install battery negative to frame.