Is it pretty straight forward to replace a EB4JS effects boa

Clint wrote:
If you look at the video I posted, you'll see a perfectl placed access panel on the Z4. This tells me that the motherboard was designed purposely for the Z series samplers. In terms of the MPC 4000 which came later, they just threw the motherboard into the casing, and said "it fits". The writing was on the wall for hardware samplers at that point so I can see why they took a shortcut.

Sad how little effort it would have taken to cut the bottom of the 4k case when they designed it.
Worse is that they sold 4k's without EB's installed.

Although in my mind the fx in the 4k are very good when delved into, in your case id be inclined to invest in the output board or adat instead and run you audio st8 into outdoor fx.That way you will have more control plus more range.