This host uses 14500 lithium cells, not CR123s (
DealExtreme: $3.99 TrustFire 14500 3.7V 900mAh Rechargeable Lithium Batteries (2-Pack))
Stainless can be worked in a "good-sized-lathe", but not much fun. In a mini-lathe, it is pretty tough.
For the 532-modules:
I have only used the O-like-modules in the Sliver-hosts,(pretty-much standard-size), but they require a special heatsink, (extended-length) and ap-cover, to provide the additional-length needed to house the 532-module, otherwise it fits fine. The DJR-heatsink is longer, and you can actually install a 532-module right into it and set-screw as usual, but an inch or so of the module will extend out the front of the heatsink. I have made a special ap-cap, which is the OD of the DJR-head, that slips-on over the module-end to cover the module and provides an enormus amount of more mass for heatsinking. I have made several of both set-ups, but I cannot accept any custom-orders for a while. We are getting our new CNC-router up and running. Check out the gallery on my site for some pictures of both.
Gallery
One other important-thing with using 532-module, make certain to reverse the battery as most/all 532-module have a positive-ground.
With regards to the Sliver disassembly, I just use a dental-pick, or other pointed instrument to gain purchuse in one of the "spanner-slots" on the "pill" that holds the driver/anode-contact board, and rotate, it should loosen-up and screw right-out.
Barry