JQuery and CFC

I have a JQuery Autocomplete working with a *.cfm file but I'm struggling trying to convert that file to a CFC.  I'm sure I'm close but could use some pointers so that I know what't going on.  Or maybe the cfc is totally wrong and I'm way off base.

Lookup.cfm

<cfset Results = [] />
<cfset LookupInformation = "" />
   
<cftry>
  <cfquery name="Lookup">
  select idnumber,
         lastname,
         firstname,
         middlename,
         suffix,
         tagname,
         city,
         state
    from Registrant
      where lower(LastName) like <cfqueryparam value="#LCase(URL.term)#%" cfsqltype="cf_sql_varchar">
        order by LastName
  </cfquery>
     
  <cfcatch type="any">
  </cfcatch>
</cftry>

<cfloop query="Lookup">
  <cfset LookupInformation = "(" & idnumber & ")" & " "
                             & lastname & ", "
        & firstname & " "
        & middlename & " "
        & suffix & " "
        & tagname & " "
        & city & " "
        & state />
  <cfset LookupStruct = StructNew() />
  <cfset LookupStruct["id"] = idnumber />
  <cfset LookupStruct["firstname"] = firstname />
  <cfset LookupStruct["middlename"] = middlename />
  <cfset LookupStruct["lastname"] = lastname />
  <cfset LookupStruct["suffix"] = suffix />
  <cfset LookupStruct["tagname"] = tagname />
  <cfset LookupStruct["city"] = city />
  <cfset LookupStruct["state"] = state />
  <cfset LookupStruct["label"] = LookupInformation />
  <cfset LookupStruct["value"] = lastname />

  <cfset ArrayAppend(Results, LookupStruct) />
</cfloop>

<cfoutput>
#serializeJSON(Results)#
</cfoutput>

Lookup.cfc

<cfcomponent displayname="Lookup" output="no">
 
  <cffunction name="Lookup" access="remote" returntype="array" output="no">
    <cfargument name="Term" type="string" required="false">
   
    <cfset var Results = [] />
    <cfset var LookupInformation = "" />
   
    <cftry>
      <cfquery name="Lookup">
      select IDnumber,
             LastName,
             FirstName,
             MiddleName,
             Suffix,
             Tagname,
             City,
             State
        from Registrant
          where lower(LastName) like <cfqueryparam value="#LCase(Term)#%" cfsqltype="cf_sql_varchar">
            order by LastName,
                     FirstName
      </cfquery>
     
      <cfcatch type="any">
        <cfset arrayAppend(Results, "No results could be found.")>
      </cfcatch>
    </cftry>
     
    <cfif Lookup.recordcount is not 0>
      <cfset LookupInformation = "(" & IDnumber & ")" & " "
                                 & LastName & ", "
            & FirstName & " "
            & MiddleName & " "
            & Suffix & " "
            & Tagname & " "
            & City & " "
            & State />
 
      <cfset LookupStruct = StructNew() />
      <cfset LookupStruct["id"] = IDnumber />
      <cfset LookupStruct["firstname"] = FirstName />
      <cfset LookupStruct["middlename"] = MiddleName />
      <cfset LookupStruct["lastname"] = LastName />
      <cfset LookupStruct["suffix"] = Suffix />
      <cfset LookupStruct["tagname"] = Tagname />
      <cfset LookupStruct["city"] = City />
      <cfset LookupStruct["state"] = State />
      <cfset LookupStruct["label"] = LookupInformation />
      <cfset LookupStruct["value"] = LastName />

      <cfset ArrayAppend(Results, LookupStruct) />
    </cfif>
   
    <cfreturn Results>
  </cffunction>
 
</cfcomponent>

Could someone point out what I'm doing wrong?  Wrong returnType?  I need to add a serializeJSON to the output?

With Lookup.cfm

$("#RegistrationLastName").autocomplete({
                source: "lookup.cfm",

With Lookup.cfc

$("#RegistrationLastName").autocomplete({
                source: /CFC/Lookup.cfc?method=Lookup&returnFormat=JSON",