I decided to remove the stock curved mainsheet traveler and replace it with a Garhauer MT-2 traveler. This was all in Garhauer's "Catalina 30 Conversion Kit" that contained traveler, risers, and all necessary blocks for traveler car and boom.
This is the old curved traveler that I was delighted to remove.
I opted for a triple block on the traveler car rather than three single blocks.
I selected standard risers (UT-1) which are designed to mount on the deck with the teak blocks removed, and hold the center of the traveler at the same level as the center of the old curved traveler. It was not difficult to remove the old teak blocks and clean up the area under them.
Garhauer's "Dodger Conversion Kit" essentially removes the camcleats at each end of the traveler rail and substitutes a turning block to route the line down to the deck, where a lift block routes the line under the edge of the dodger to a rope clutch adjacent to the companionway.
I made a teak wedge that positioned the lift block at the correct angle with the block above, and that covered the old holes in the deck (except for one hole in the slant of the hatch rail which was filled with a teak plug.)
Each line terminates at a Garhauer rope clutch under the dodger alongside the main hatch.