I timed both taking the bus from that lot, and walking from the Homewood next door over two days.
For the bus, we left the Hilton Homewood at 6:45am and walked to the parking lot entrance on Harbor. There is a footpath to the left of the entry kiosks that all the waiting cars are lined up at.
At 6:50pm they opened the pedestrian entry gate, and we walked through the parking lot to a very short line of people waiting at security. Walking in we beat all the cars to security as they weren’t let in until 7am or just before.7am.
Security opened at 7am and we were on the first bus arriving at
Disneyland around 7:12am. Lines at the ticket gates were already somewhat long.
The next day I left the hotel at 6:30am and walked to the Parks along Harbor Blvd which took 15 minutes. There was a small line waiting at the tent for security to open at 7am. Once that opened I was through security and in a short line at the park entry gate.
Walking up was better in the mornings if you are willing to leave the hotel at 6:30am.
Either way you are in the parks for rope drop.
We always took the bus back at night.