I have the TL3500P big blue. Love the light, it’s awesome but have struggled with Goodman handle. On my fourth option and I think it’s a winner! Like others suggested, go with Dive Rite QR handle and their generic mount that uses cable ties. The handle comes with spare longer screws. I used one longer one which goes through the mount and into the threaded hole on the BigBlue. Thread is wrong size, but having the longer screw poke into the hole it helps prevent the light sliding forward/back.
Then I added a bungee to the goodman handle, so that when wearing it bungee goes behind base of your hand and it holds everything in place. Don't need to hold onto goodman, it just stays in place but is super simple to pull off and change hands if needed.
Additionally I have CX2 as backup light clipped to my harness. So if I need to switch it is quick and easy and I don't need to remove my goodman handle from hand at all to do it.
Here's the parts
Dive Rite QRM Goodman Handmount w/Locking Receiver ONLY
Dive Rite QRM-UNI Striker Only for Universal Lights
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