I'm looking for the marker or pen used to write the RPO codes and markings on the firewall of my 62. I had "293" (RPO for the 261) "4S" for 4 speed, RC for recirculating heater, "C1534" for 1/2 ton LWB fleetside and a couple of others. All were in black exept for one which was white. Can anyone tell me where to find this kind of marker? I opted to strip and paint but can duplicate from pictures. Can anyone tell me what "A126" means or "196"? These are two I cannot identify. Thanks.