There were TWO different packages of Microcuts @ Home Depot
08720-VLOPS00
Replacement Blade Set for Honda HRR Models with Clip Director
HRR2169PKA
HRR2169VKA
HRR2169VLA
HRR2169VYA
Are these the proper set ?
Look on the serial number plate (rear of the mower deck) on your mower. The full model name will be there. If you see the "9" in the name, you got the right blades. If not, you should return them and get the factory-recommended blades that match the ones that came with your mower. Look for part number 08720-VE2-001.
What is a Clip Director ?
A small door/shutter that lets you choose to mulch or bag. It's a green lever on the rear of the mower deck. If you do not have one, you for sure do not have have a K9 mower, and need the different blades.
Does one need to use a NEW washer every time ?
No. The washer is curved and has some spring built-in. Compare an old one to a new one. If they are the same shape, you can use the old one. Eventually, the old one will start to get flat (no spring) and should be replaced.
Why remove the spark plug cap ? The engine can't start by itself.
When working around the blades, you just don't want to take any chances. Disconnecting the spark plug cap is 100% effective against any possible accidental engine start.
What happens if the center bolt is removed but the tightened back on ?
Provided nothing else fell or or came apart (varies with models) just tighten it back securely. Not usually an issue.
The box directions could be improved: "The smaller blade goes on top? The "on top" is not defined and seems to contrast with "the smaller blade against the engine". Against the engine ? Huh ? Does Honda mean "closest" to the engine ?
Typically, you'd tip the mower over on its right side wheels to service the blades:
"smaller blade" = thinner blade = upper blade = "blade against the engine"
The upper blade sits 'on top' of the lower blade.