loop to disable radio buttons

[jamica]

I have the follwoing javascript(the html's below)...... I am trying to disable the radio buttons in all radio groups which will total to more than 4 i've managed to get it to get a total of 4 but i now need to disable the radio buttons which will give a higher value than 4 ie if 3 is checked then the user should only be able to select 1 from the rest of the questions....

how do I get it to loop and disable all radio options which will total to more than 4?

thanks

<script language="JavaScript" type="text/javascript">

// function which works onClick of a radio button to find out which radio buttons to make void 
function workOutSpotsAvail()
{
	//array to hold the available radio buttons 
	var spotsA	vail = new Array(4, 4, 4, 4);
	var valChecked = 0;

	// Loop through question
	for(option=0; option<4; i++)
	{
		// work out the value checked
		for(optionVal=1; optionVal<=4; optionVal++)
		{
			var currentRadio = getelementbyid("ol_" + option + "_" + optionVal);
			if(currentRadio.checked())
			{
				valChecked = optionVal;
				break;
			}
		}
		
		// Remove value from other options
		if(valChecked > 0)
		{
			for(i=0; i<4; i++)
			{
				if(i != option) spotsAvail[i] = spotsAvail[i] - valChecked;
			}
		}
	
	}
	greyOut(spotsAvail);
} 

// disables the radio buttons which are rendered in the last function 	
function greyOut(spotsArray) {
	


}

the html

   <form name="forms" id="forms" method="post" action="3.php" onsubmit="return validate()">

      <input type="radio" name="o1" id="o1_1" value="1" class="check1" onclick="workOutSpotaAvail(1, 1)" />
        <input type="radio" name="o1" id="o1_2" value="2" class="check2" onclick="workOutSpotaAvail(1, 2)" />
        <input type="radio" name="o1" id="o1_3" value="3" class="check3" onclick="workOutSpotaAvail(1, 3)" />
        <input type="radio" name="o1" id="o1_4" value="4" class="check4" onclick="workOutSpotaAvail(1, 4)" />
        <br />


       <input type="radio" name="o2" id="o2_1" value="1" class="check1" onclick="workOutSpotaAvail(2, 1)" />
        <input type="radio" name="o2" id="o2_2" value="2" class="check2" onclick="workOutSpotaAvail(2, 2)" />
        <input type="radio" name="o2" id="o2_3" value="3" class="check3" onclick="workOutSpotaAvail(2, 3)" />
        <input type="radio" name="o2" id="o2_4" value="4" class="check4" onclick="workOutSpotaAvail(2, 4)" />
        <br />

        <input type="radio" name="o3" id="o3_1" value="1" class="check1" onclick="workOutSpotaAvail(3, 1)" />
        <input type="radio" name="o3" id="o3_2" value="2" class="check2" onclick="workOutSpotaAvail(3, 2)" />
        <input type="radio" name="o3" id="o3_3" value="3" class="check3" onclick="workOutSpotaAvail(3, 3)" />
        <input type="radio" name="o3" id="o3_4" value="4" class="check4" onclick="workOutSpotaAvail(3, 4)" />
        <br />


       <input type="radio" name="o4" id="o4_1" value="1" class="check1" onclick="workOutSpotaAvail(4, 1)" />
        <input type="radio" name="o4" id="o4_2" value="2" class="check2" onclick="workOutSpotaAvail(4, 2)" />
        <input type="radio" name="o4" id="o4_3" value="3" class="check3" onclick="workOutSpotaAvail(4, 3)" />
        <input type="radio" name="o4" id="o4_4" value="4" class="check4" onclick="workOutSpotaAvail(4, 4)" />