Pinging (Spark knock)/ EGR

[Dnailer]

Hey guys. Could use some help on this one.
1987 Ram 50 2 wd 2.6l 5 speed.
EGR light has been on in this thing since I bought it and its pinged ever since I bought it so I'm assuming that its related. I replaced the EGR valve and all of the vacuum lines as well as having tried running a higher octane fuel as high as 93. The EGR light is still on and the engine still pings when under a load.
Can somebody help?
Is it related to that little box mounted on the driver's side fender that the largest EGR valve line runs to?

[camoit]

I think behind the dash cluster there is a little switch that you move to reset the EGR light. Pull the cluster and you should see it. Use the search box at the top of the page. I'm sure someone else has see this befor. As for the pinging you might want to go with 92 octain gas. And back the timeing down a degree or two. Thy the Gas first. it might suprise you. Mine did the same thing. New gas fixed all that pinging. Let us know

[beachrat92]

you dont have to pull the cluster. on the right side of the steering wheel is a little black switch cover (opposite of the hazard light) pull that out and look it in there is a little switch flip it the other way. the light should go off