I've never been able to confirm the Corvette 235 story, there were many differences in the Corvette versions - different heads, block castings etc, even running changes between '53 & '54 versions but it seems the factory didn't publicize or document what went into these engines, or at least I haven't been able to dig it up. The Vette 235's were tuned for higher RPM - they definitely used dual-wound valve springs, solid lifters, and a different camshaft - so beefed up rods would make sense.
The 261 rods are the same length and the big ends are the same, but the wristpin bores are larger than the 235. GMC rods can be modified to work - big ends have to be narrowed - but require cu$tom pi$ton$ due to different compression height. So it seems there are no easy alternatives, at least affordable ones.
