LOL..I guess your right. I have a 57' Marlin and had to tap the receiver myself. But as far as hammer extension...I had at least 3 different ones over the years...nothin but problems. HiRise mounts worked out much better for me...and with the see thru feature I could still use the irons for close range shots.wreckhog said:336 have been factory tapped for scopes for 50+ years. A Weaver scope base from wherever, and Weaver Quadloc rings and a Nikon 2x7 from Walmart are hard to beat for well under $200. A slightly cheaper (and vastly inferior, yet quite popular) option is the Bushnell Banner 1.4-4.5 or Simmons Pro Diamond 4x. Adding a hammer extension is a bit safer for decocking, I don't like high rings. Sky is the limit on $ though, and more $ creates a lot of options.