Somehow while looking into an add a zone for work, I stubbled upon this article. It was great, except too many had negative to say. I did the very thing about 8 years ago, except I didn’t get into the drawing detail too much. I already new how the overlap works and the nozzels I needed. The one think I did a little differantly was I used my ols water hose. Found the 90 degree hose barbs at the farms store, hose clamps, made the narrow ditch like you did andI am in business. Another part I added later was to disconnect from the from faucet and bury pvc to the back faucet. Now for the fun part. Had an old Hot tub I need to get rid of. Took the motor and pump, plumbed to the back faucet. Well, you can probably picture the rest. Now with an electric valve in line and a timer I can just swith valves from front to back and I just love to most even coverage you can imagine. Hope anything I wrote helped someone.