JSFiddle - React, Tailwind, and code Playground

HTML

<select name="service" id="type" onchange="findselected()">
    <option value="Not Selected">Select Service Type</option>
    <option value="Residential Service">Residential Service</option>
    <option value="Commercial Service">Commercial Service</option>
    <option value="Industrial Service">Industrial Service</option>
    <option value="24/7 or Emergency Service">24/7 or Emergency Service</option>
    <option value="Automotive Service">Automotive Service</option>
    </select>
        <input type="text" name="model" id="model" style="margin-left:83px;" class="text-box" autocomplete="on" disabled="disabled" value=" "/><br /><br />
        Model Year:
        <input type="text" name="year" id="year" value=" " disabled="disabled" style="margin-left:73px;" class="text-box" autocomplete="on"/>

JavaScript

function findselected(){
var state = document.getElementById('type');
var notus = document.getElementById('model');
var year = document.getElementById('year');
var maker = document.getElementById('maker');
notus.disabled = (state.value == "Automotive Service") ? false : true;
year.disabled = (state.value == "Automotive Service") ? false : true;
maker.disabled = (state.value == "Automotive Service") ?  false : true;
}