I’d simply ‘T’ into existing wiring for the new jets. Solder in new wires into existing ones.
So you will have both old connector and any new connector you can imagine to connect new stuff.
So that old and new connectors are not mutually exclusive and you will always be able to return to old jets if you want to.
For experiments I’d simply tee wires with naked ends and will do experiments without thinking too much about the fancy connectors.
When you decide about the right jets we can talk connectors.
Hope it makes sense
