Your truck is a perfect candidate for a donor car swap. Choose any 90's Chevrolet car or truck that has an LS motor. Buy the whole vehicle and use all the mechanical and electrical parts off it, then sell the remaining sheet metal, glass and interior to recoup some of the cost of the donor. Make no changes to the motor or any other parts. Put the stock motor, transmission and differential into your truck, with all OEM wiring from the donor. I can see 300+ hp for $1000 to $1500 cost of the donor. Lots of work, but you have to discount your labor on a project like this.

And no, Chevy heads will not fit an Olds block.

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