Suggestions here? To Deadend the Port and starboard control lines or use a continuous loop (this is an option with double stacked end sheeves) and how much slack.
My overhaul of the new ball bearings and pin straightening was successful (66 x each side)now it works so well I cant believe how nice this device is!
Last year it it barely worked, It had continuous loop with very little slack.

I'm in the middle of rebuilding my Harken traveler and have purchased the windward sheeting car conversion kit. I also loaded new torlon bearings in the car. My plan is to start with 4:1 control lines in a continuous loop. The loop will have about 24" extra. I also will run the traveler through an eye outboard port & stbd with jam cleats. This allows the outboard cleats to be used to stow the traveler since Harken recommends something similar when on a mooring or in conditions where wave motion in light air may cause the windward sheeting car to slip.

This gives me two options, both that shorten the traveler control lines if I find I don't like the setup.
1. Shift from 4:1 to 3:1 as a result of bypassing a block and moving the end point termination from the center to the edge.
2. Cut the continuous loop and go single ended on each side.

So I recommend buying sufficient line to run continuous with a couple feet extra. Try it out, then see if you like it. You can always cut the line to shorten it if you don't like the setup.

It's conceivable that the continuous loop would reduce line clutter in the cockpit but at the expense of a free running system. 3:1 with the Harken windward sheet system allows a quick dump all the way to the bottom of the track in puffy conditions and a one handed trim.

We kept the Harken 223 double upright bullet blocks from the previous system but after a while replaced the cam cleats with eyestraps to dead end the traveler line and keep it close at hand.

If the boat is in motion at the dock or mooring, as the boom swings it will open the cam cleats on the traveler car, first one side then the other. This eventually bends the posts on the underside of the 150SP a $50 part. Try pulling the traveler to one side. Then loop the traveler line around the jib cleat, back around the line of the mainsheet purchase and back to the jib cleat with the traveler line.