How much should a basic 340 rebuild cost?

So you don’t gap the rings? Verify compression?

Mic the crank and measure the bearing clearance?

Degree the cam?

That’s minimum **** that needs to be done. And it takes time.

You either cut corners or you don’t value your labor.

Neither one is a good thing.

But it’s ok in your book because it’s just a stock 340.

Got it.
Did all that and more in an afternoon.