I think what he was saying, if you use 273 rockers, you will have to use a mechanical cam. The Mechanical cams where used up till mid late 60's..? Not exactly sure on years, Your 360 I'm sure has a hydraulic cam. Here is my suggestion for your dilemma. I had the same problem that happened to you, on my stock 68 318 truck. I went down to car quest and bought 2 rockers. (the intake and exhaust rockers are different). I replaced the 2 and it worked for years until i sold it. Or you can replace all 16. They actually had them on the shelf. I payed 6-7$ a piece, so your looking at 100-112$, but you will have all new original style rockers. They are fairly easy to replace, no adjusting, just put the rockers on and torque the bolts down. Hopes this help's