Here's a method that was devised by marzach. I had the same type of problem on my '47 that you've encountered on your '50. I've attached some before and after pictures for your review.
Installing Cab Windlace without Kinks Here’s a great Tech Tip from Charles Smith (marzach) on how he installed cab windlace without any kinks. To get your cab windlace installed without kinks in the upper rear corner, here is the procedure that worked for Charles. Begin by cutting a 14 inch section of 3/8 inch nylon rope that has a very tight weave (3/8” is a little larger than the inside diameter of the windlace bulb) and a heavy pull cord a couple feet longer than the total length of the windlace. The pull cord I used was nylon and slightly larger than a pencil lead. Melt one end of the nylon rope and grind down the melted outside edge area to the same diameter as the rope. This will give the rope a little more strength for the following step. Tie a small knot in one end of the pull cord and with air pressure blow it through the full length of the windlace bulb. Attach the other end of the pull cord to the melted end of the rope about 3/8 of an inch from the end. You will have to punch a hole in the rope to attach the pull cord so the pulling motion will not be off center. Measure and mark the windlace area that will be at the upper rear corner (the area which is prone to kink during installation). With a person on each end of the windlace, pull the nylon rope into the section of the windlace bulb that will end up in the prone to kink corner. There will be a slight interference fit when the rope goes into the windlace bulb and will remain in the area you place it. The nylon rope will retain the original shape of the windlace as it goes around the kink prone upper rear corner during the installation process. The pull cord will remain in the windlace with no ill effect, just trim off the ends as needed. You might want to have a pull cord at both ends just in case the primary pull cord comes loose or breaks, so you can pull the rope back out and try the process again. Otherwise, the rope will have to remain where the pull cord comes loose. I applied a little Vaseline to the rope before installation. I used Jim Carters grey windlace and was able to get both sides installed without any kinks. I hope this windlace installation procedure works just as well for you.
