which slot do I use...?

[Questar]

I have a 9150 server (nubus) with a video card in slot #4. I have a core system (i/o and farm) in slot 1 & 2 and an additional i/o in slot 3. If I install a second dsp farm, can I use slot #5 (skipping #4) because slot 5 has no opening in the back of the cpu to allow cable access and video card requires rear access. If anyone can help me please email me at QR2R@aol.com
Thanks