If a 5.3 from an H3/Colorado will fit but may be too much power for the stock tranny, what about the 3.7 from an H3/Colorado. the 3.7 makes 242hp and 242 ft lbs of torque.
That H3 swap would be best to find a salvaged one and just transplant the VX body on top of everything else! (I had the same thought with a Chevy Duramax single cab short bed with the Duramax Diesel and Allison transmission!)Lots less work that way, though the frame rails may be right at the door sill
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