What suspension upgrades should i do for $1200 big block dart

I am definately going with sub frame connectors ,Do you think the bolt in frame connectors would be ok?

As a subframe connector the Mopar Performance bolt-in connectors are ok, but only if they're welded in. If the welding is the problem, you can bolt the connectors in yourself so that you're happy with the location, and see if you can talk the local exhaust shop into welding them in. They'll have a lift and a welder.

I was thinking the Hotchkis rear leafs

I've seen some mixed reviews on them in the past. The most recent installs using the Hotchkis springs seem to be better, maybe they sorted some things out. Ride height will be pretty low, I think @MuuMuu101 is the most recent person to use them on a build. This is the ride height on his car.
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