Up until the late 60's, all the 1-A clears and some 1-B stations were still petitioning the FCC for higher power. They were grouped together as the Clear Channel Broadcasting Service.A few clears followed WLW's lead and requested 500kw. Only WLW was approved. (I'll try to check WLW's card to see if there was any difference in the wording.)
Here is a collection of their documents: https://worldradiohistory.com/WSM_Clear_Channels.htm