Here's how I got the lower nuts between the turbo and the collector housing:
I just heated & bent a 15mm box end wrench, cut it off, and welded on the cut-off end from a 3/8" drive extension. It worked great!
After much cussing, my eventual sequence of events was as follows:
1) Remove lower downpipe bolts from both sides (where they attach to the exhaust manifolds).
2) Remove turbo inlet hose and outlet Tee.
3) Remove downpipe clamp.
4) Remove EBPV
housing (mine was already gutted so I didn't have to deal with the linkage rod). Definitely needed a 3/8" drive 12-pt 8mm socket for this one.
5) Remove all but the driver's side rear up-pipe to collector bolts, working from above initially with a box end wrench, eventually with a 1/4" drive socket.
6) remove top bolts and lower nuts connecting the turbo to the collector (using home-made wrench pictured above for the nuts).
7) wiggle the collector and up-pipes around, and push the collector back towards the firewall.
8) Use a 3/8" drive 10 mm swivel socket to remove the bolts holding the pedestal to the engine (you need to get to step #7 to allow the use of a 3/8" drive on the driver's side rear bolt).
9) Use a box end wrench to get at the last up-pipe to collector bolt.
10) Slide collector off of up-pipes.