DIY green laser in a C6 host

I'm most of us have seen this video at some point: Homemade DIY 532nm Green Laser in C6 Host - YouTube

Good to see it's so easy to put one of these together, although I wonder two things:

1) What size is the lens thread; I can't tell by looking at it. 12mm module so it must be smaller than that. Is it a 9x0.5mm? If so, can I replace the lens barrel with a longer one and an AixiZ or other focusing disk?

2) It's clearly case positive (ugh, that GODAWFUL battery...) but I want all my C6's to be case negative for consistency. Any way to do that with that laser? I'm guessing I'd need to isolate the heatsink/module from the host and that I'd be better off just making some mark on the host to remind me that this unit is case positive and not negative.

Or, could I use a flexdrive to power the pump diode? Hmm. Measure current output of stock driver, set flexdrive to same, and then run it case negative?

Maybe go with the extended/tapered heatsink to provide extra fall protection to the front end, since I tend to be klutzy and drop my lasers sometimes.

Oh well, random thoughts.

I have no idea on the lens.

As far as I know, and experienced, the entire host is anodized except for the pill and the threads so the heatsink is electrically isolated. You need to use a contact board if you want it to be case negative. You have to find the positive pin of the diode and connect that to the center of the contact board.

It did look like there was a white wire sticking out of the host at one point, I bet that would explain it. And then wire the spring to the contact board negative. That simple, really?

Yes. You may need to remove the spring to make some room for the contact board.

Definitely appreciate the info, the C6 host I have includes the drilled pill and battery contact board.

I've been looking at ebay seller techhood's offerings and there's some nice looking stuff there. I'm worried about how far the module is going to stick out of the front though, which is why I'm wondering if I could use a flexdrive in place of the battery board and delete the stock driver entirely. If I did that, I could fit one of the 200mW modules without issue. Any thoughts on that?