I have a network of around 60 SXTs, and many of them used as routers are set up for convenience to have the 192.168.88.x IP range as their internal addresses. I manage all the SXTs via 192.168.2.X addresses, and winbox neighbour discovery works fine using L2.
Now I have three further SXTs that are connected via one of these routers with the 192.168.88.x range. The SXT that links to my network (call it extrouter) is then connected to clients's LAN, and off that LAN I have one SXT as an AP bridge (192.168.88.4 - call it intbridge) and two as stations (88.5,88.6 - call them A and B) that have been configured as routers with 192.168.89.X and 192.168.90.x as their private LANs.
I have been trying to use three EOIP tunnels to extend the management L2 so that I can give these three 192.168.2.x addresses connected to the EOIP tunnel. It almost works, but there are some oddities I don't understand and would apppreciate some feedback.

1) In intbridge I give eoip tunnel 2.x addess, and in extrouter I bridge the wlan and eoiptunnel1 to intbridge. Works fine - I can see 2.x address of introuter in winbox.
2) In A I set up another tunnel to extrouter with 2.x address and add that to the bridge. Get lots of loop errors in bridge and things don''t work even though bridge in extrouter has none as protocol mode. Detach eoiptunnel2 from the bridge and bizarrely it works almost perfectly - I can see intbridge and A (and later, B) with their 2.X addresses and winbox finds them. It's almost as there is only one eoip tunnel instance, and if you bridge one then you bridge them all?
3) winbox discovery isn't perfect. SXT A announces its own MAC, while SXT B announces the private MAC I gave the tunnel. extrouter announces all three private MACs I gave the three tunnels, one with the correct external address and the other two with 0.0.0.0, and the proper MAC with the internal IP 88.1. So this now appears four times in total.

Any suggestions?