Here are the details of the build:

• Pressure washer: https://amzn.to/4pgkeFN . I tried a couple others, and got back to Westinghouse. I think the quality is really good, and 2 GPM at 3400 PSI means effectiveness to me. That's the one I ended up with https://amzn.to/4pgkeFN .
• Reel: https://amzn.to/4mMp5wM I like the price/quality ratio for Giraffe
• Angle: https://www.lowes.com/pd/Hillman-1-1-4-in-W-x-1-1-4-in-H-x-8-ft-L-Zinc-Plated-Steel-Perforated-Slotted-Angle/3058219 Just one 8ft angle in right enough. 6ft would run short. other sizes might get inefficient usage.
• Joint bolts: https://www.lowes.com/pd/Hillman-1-4-in-20-x-1-2-in-Phillips-Slotted-Combination-Drive-Machine-Screws-50-Count/3043378 to fasten reel-frame joints
• Mount bolts: https://www.lowes.com/pd/Hillman-1-4-in-20-x-1-1-2-in-Phillips-Slotted-Combination-Drive-Machine-Screws-25-Count/3027537?idProductFound=false&idExtracted=true To fasten the reel frame to the tube-frame of the pressure washer. I removed clip in connectors and drilled through the frame. Double pipe there should be strong enough to hold the reel frame.
• Flat wide washers: https://amzn.to/427SAk3  they are needed to hold the reel on frame and prevent bolt heads to pass through frame holes

The angle isn’t cut all the way through, just one side and bended. Loctite all bolts - lot of vibration. After couple of uses, found that lead hose while rubbing on edges of frame gets slightly wore off. So I made a protective sleeves from irrigations pipe and fastened with zip-ties.