The halyards in this kit are suitable for use on legacy Catalina supplied masts or later Charleston Spars supplied masts. It is not suitable for use on a furling mains'l halyard on a later Selden mast as that rig requires a special eye splice. It cannot be simply tied to the shackle as on earlier spars.

Catalina Yachts never spliced any halyard prior to the use of Selden rigs. It was simply tied onto the halyard shackle including the shackle for the Charleston Spar furling mains'l swivel.

We are aware the original Charleston Spars mast manual refers to an eye splice for the main halyard. But Charleston Spars did not supply the halyards. Catalina Yachts supplied the halyards. They never employed anyone whose job it was to splice lines in the rig shop. The dealer tied the shackle onto the halyard when the boat was comissioned.

A prior owner may have spliced the halyard. But that will only work if you use the wrong line. Your masthead is not wide enough to accommodate the fat part of a splice. If you use Dacron line, it can be spliced with a short bury so the fat part of the splice never reaches the masthead. But all Dacron line including Sta-Set and Sta Set X are too stretchy for halyards on a C-34 or C-36. Use a proper Spectra or Dynema core line and the splice must be long enough that the fat part will jam into the narrow slot in the masthead unless the luff of your sail falls significantly short of the masthead. 

The legacy Catalina supplied masts were designed for use with wire rope. They were never intended for use with all line halyards. There happens to be enough room for the line, but not enough space to accommodate a splice.