Piston and con rod dilemma

I'm using the kb 243 in my 340 expect I had a 72 340 that had all original stuff so I re used the rods and had new apr rod bolts install and big end resized. Got a old factory forged crank that cleaned up at .010 under.

It has 3,000 miles now in its first year, seems as tight as when new. My rev limiter is set at 6,500 thou. Needs a larger cam but got other stuff to do