Two tips on contacts and spacing:
measure up a cm and cut away part of the tube, leaving a d-shape hanging down. More specifically...
Cut at widest diameter along length both sides, like splitting a banana for a sundae... about 1/2", then stop.
Cut away one side of the tube, leaving the hangin'-down thang to drill a hole thru and affix yer lead.
Developing this thought further, use a strip of 26-30 ga stainless, bolting one end to the tube flange and the other... take it down and bend a 90' inwards leaving a 3/4 flange. Poke a hole in that, and bolt thru the endcap of cylinder. Repeat for each outer tube. Tie together electrically outside the cell.
Now fer spacing, I got some 1/8 and 1/16 neoprene gasket sheet and sliced off little pieces. I also got some 1/4 rubber from some dumpster dive somewheres... anyhow I sliced carefull thicknesses tha twere cut to 1" lengths, and when the right thickness was found, I placed two pieces 120' apart, and shoved the inner tube over and cram-rammed the third piece at the third point.
Pic+ 1000 words... here's showing rubber, not the notch contact idea.
Worked for me, but I've only run these in Faraday. My clone is gonna hit 'em with Meyer drive later next month.
Turtle