Here's my latest variation on tube cleats. I discovered PVC is very willing to bend with minimal heat. I use a hot air gun like those used for scraping paint. Since it is more rigid yet movable, it is much easier to operate with one hand. The PVC costs about 15 cents.
Greatest cost is the stainless bolts to mount it to the frame.
Heat and pliers create a nice flare to allow the line to feed in smoothly. I matched the angle to the line that feed into it from the bridal over my transom. Experiment with different sized tubing and slots for the line you're using. I have one on either end. For slippery line take a turn around the seat before jamming.