11/44 -> RL11

Hello ListFriends... Further along the path of getting RL02s attached to my 11/44 system: Given a stock 11/44 in a KD11-Z minus the CIS and FPP modules: the last two slots, 13 and 14 are SPC slots. In my system, there are two more backplanes installed and in use. Memory slots 11 and 12 are occupied by G7273 double grant cards. As configured [and working fine], slot 13 has the Emulex TC12 (which is a quad-height module), and slot 14 hosts an M9202 bus jumper and a grant continuity card in "D". OK: I want to put an RL11 (hex height) in slot 13 and move the Emulex card to 14. I did this twice... once with the RL11 in 13 and the Emulex out of the box, grant card in it's place... the error message on boot was: ?20 MPC=15 The second try was removing the grant card in 14 and inserting the Emulex therein.. the error message on boot was: ?22 CPU HUNG Restoring the system back to Emu in 13 and grant card in 14 restored the system to normal. I am currently dragging the box out of the rack to check the NPR jumpers, the RL11 doc is pretty specific and clear on what to do... but I have no Emulex docs so I'm kinda lost there. Am I barking up the right tree(s) so far? Bonus question: the system is configured with (3) M5904 MassBuss cards which I am not going to use right now.. if they are removed, other than the grant cards needing to be installed... is this going to cause havoc? Thanks y'all Cheers John