Just wanted to thank the OP for the original thread and pictures. I completed my diesel purge cycle this evening. Took about 10 minutes to get the lines off and the temporary lines on. I used 3/8" on the pre-filter side by removing the plastic from an old fuel line and just using the tab that inserts in the top of the prefilter. I used 1/2" on the back of the filter housing as in the pictures. Worked great and the engine runs and feels a good bit smoother tonight. It might be wishful thinking but I hope it helps.