Do you have an external, powered SCSI hard drive or drive case?
I gave that a go with similar results to just leaving the HDD in. I can't remember if I could have more RAM or not.
I may have access to NuBus connectors at my local surplus store (I'm going to go check today.)
Oooh }

How many, and at what price?
I found two male connectors and a whole box load of female connectors. They were 90 cents each I believe.
on the card, disabling the pins underneath
How?
Looking at the NuBus connector, I think I can straighten the pins and pull them out of the housing so there're no pins at all that would connect to the motherboard's slot. I would then solder the molex cable directly to the board's 5v thingy, and the ground to the ground pin.
Where does the added Nubus connector come in here? Does it sit between the Rocket and the motherboard Nubus socket? If so, will you still be able to close the case with the added height on the Rocket?
I think I misspoke. I meant to have an extra NuBus connector so that when I'm done fiddling, I can put a new one back on so the card still works. I'll be making some permanent changes to the NuBus connector itself and I wanted the card to still be in working condition if my idea doesn't pan out.
I do like the idea of a self-powering Rocket mind you
If I have time, I'm gonna give it a go this weekend.