Edit: Saw you already found a spacer
Maybe not ideal but I actually bought 1x 16mm and 3x20mm copper mcpcb and proceed to delaminate the top with heat, sand and solder these sandwiches into a tall spacer. Then drill a hole in center.
Quite some tasks but hey it is still cheaper than buying a spacer or getting a Jaxman E2L host in the past.
Quad is fine. I’ve been thinking about it too. But I am not sure how big is Kaidomain’s Quad TIR diameter. I only know the triples will fit the S2+ but not sure if it’s too small for S21A or too big for S2+
There’s also intl-outdoor if you need any parts like carclo. They used to have triple mcpcb too but not much now.
Glow gaskets. Maybe follow” CRX guide”:DIY Glow Gaskets for Triples and Other Glow Stuff on how to do it but with glow tape? Or scour around aliexpress resellers for turboglow?
And as for driver I still run convoy’s SST40 driver. This one
Probably my favorite since I don’t really change mode often. Just program my favorite brightness into 3 slots and I got 3 useful preset and no memory. Although it can hit 8 amps, it will probably go at most 6 amps in my case. 5 amps nominal.
The driver you linked is a 20mm. S2+ only fits 17mm