Grounding Question

Hi, I'm working my way through my harness design and have a quick question re grounding. At the moment I'm looking at one of two options

1. Run ECU grounds from the cabin through the bulkhead connector, and ground these, and the ignition coil ground wires, to the same point on the engine block. The block is earthed to the chassis, and the chassis to the battery. I am also using a Link Razor PDM for power supply (injectors, coils, flex sensor, H bridge supply, fuel pump - things like headlights I am just going to leave on the factory power supply circuits) that would be in the cabin, and grounded to the chassis inside the cabin.

2. Run the ignition coil ground wires from the engine bay back into the cabin via the bulkhead connector, and then ground the ECU grounds, the coil grounds, and the PDM ground to the same point on the chassis in the cabin. The chassis is then earthed to the battery. In this scenario all of my sensors and power supplies are earthed via the harness to the chassis and from the chassis to the battery. I can't see a need to earth the block - the factory knock sensors earth to the block but as I'm now using bosch wideband that I believe earth via the sensor ground I can't see a need to add a chassis ground to the block?

Is there a preferrence? And why?

On one hand I prefer option 2 as I don't need to build an earth point into the engine bay side of my wire harness. Although it does create a bit more work and packaging demands on the other side.

Thanks in advance! Any feedback is very much appreciated - I'm trying to learn as much as I can about what is considered best practice.