Timing Chain Oiling Confusion

I recently disassembled two 70 model 340's. One motor had the 2 top bolts drilled out that hold the cam retainer on to allow oil from the valley to drain on the chain and was assembled with a slinger. The other had no slinger or drilled bolts but has a tab that bolts to the bottom bolt on the retainer. I'm guessing it is a scraper. What is the correct? I'm trying to put one motor back together. Any help would be appreciated. Thanks Jeff