That question is at least part of Bunsen's impetus to a clone-the-IIcx-adapter question above, I suspect. Yes, the IIcx and SE/30 both have 16MHz 030 processors from the factory, so it is electrically feasible. However, physically, the IIcx adapter fouls the battery cage, power supply socket and native 030 PDS slot on the SE/30's MLB, at least. Further, the on-card IIci PDS slot is then (seen from the front of the SE/30) left of the centre-line of the MLB.
The necessary traces and components of the IIcx adapter could be arranged on a smaller card, because the constraint of extending the on-card IIci PDS slot from under the IIcx's PSU would no longer exist, but it would still be necessary to modify an SE/30's chassis to clear the card. If the male 68030 CPU plug on the underside of the adapter could stand higher off the card, the battery cage could be cleared by a cutout from a 6" x 3" card, and the adapter card could also clear the PSU and FDD connectors. The real crunch is that the position of the on-card IIci PDS slot would still be awkward to arrange while keeping it parallel to but far enough away from the SE/30's 030 PDS slot and the CPU plug. So it is physically a pain.
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The necessary traces and components of the IIcx adapter could be arranged on a smaller card, because the constraint of extending the on-card IIci PDS slot from under the IIcx's PSU would no longer exist, but it would still be necessary to modify an SE/30's chassis to clear the card. If the male 68030 CPU plug on the underside of the adapter could stand higher off the card, the battery cage could be cleared by a cutout from a 6" x 3" card, and the adapter card could also clear the PSU and FDD connectors. The real crunch is that the position of the on-card IIci PDS slot would still be awkward to arrange while keeping it parallel to but far enough away from the SE/30's 030 PDS slot and the CPU plug. So it is physically a pain.
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