The punch tool
You know the drill
Here we start putting the holes in the case. Yeah, this shot is a bit sloppy, but it works. We didn't have much scrap wood around, so we didn't really have a good way to support the motherboard tray. I would highly recommend getting a piece of particleboard that's bigger than the tray. Due to the pressures and forces you'll be putting on some parts of the chassis, you're definitely going to need something to support the metal so that it doesn't bend or warp.
Tapping the screwholes
Without a good way to secure the motherboard while we're tapping the screwholes, we ended up just closing the chassis back up and tapping them from the outside. This certainly wasn't the preferred way, but without a good way to support the tray while we're tapping holes, this was really the best way to do it.
Removing the original standoffs
The original G4 motherboard mounts were taller than the motherboard mounts in places, and plus, they're grounded to the chassis. If they were to come in contact with any of the solder points on the motherboard, it could be Bad News(TM). We needed to go ahead and get rid of them. It was quite messy when all was said and done.
Before the cleanup
The Dremel cutting left a lot of metal dust and particles around the chassis. We used a few rags to protect the inside of the chassis while we cut off the tops of the standoffs.
The locking sheet
Since we inserted the new motherboard standoffs into the mounting tray, the plastic sheet needed a few new holes. We went ahead and took the detached plastic sheet into the garage for a couple more holes. Unfortunately, I failed to recognize the "mobile" nature of this plastic sheet. More on this later.
The new holes
This picture shows more clearly the two extra holes I drilled into the sheet to make clearance for the motherboard standoffs. They're showed to the far left and the far right.
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