K member modification ?

340/360:
Engine Performance & Vehicle Customizing Products From Hedman | Hedman Performance Group
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Engine Performance & Vehicle Customizing Products From Hedman | Hedman Performance Group
B/RB:
Engine Performance & Vehicle Customizing Products From Hedman | Hedman Performance Group
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Engine Performance & Vehicle Customizing Products From Hedman | Hedman Performance Group

You can also mount a small block by using an A body/LA motor engine bracket on the driver's side, and an LA motor truck bracket on the passenger side.