Yep......anyone that has built a big power Buick V6 has run into this. Usually all it is is the actual rod bolt that sticks out, too far on the top side. (threaded end). Torque the rod to full value (in a vise using a stretch gauge) and then grind smooth to the rod. May take a bit more off of the rod, too. And because it is on the rotating end of the rod, you shuld have them re-balanced. Take it back to the orginal balancer and it'll be pretty easy for them to fix it. Also check the rod bolts for clearance with the bottom of the cylinders, too. (socket side of the rod bolt) They usually hit there, too. Also check the top of the rod to the bottom of the pistons. It can get a little tight there. Always mock up all the rods, pistons (w/o rings), crank, timing chain, gears (properly degreed in) and give it a spin and use a small mirror and bright flashlite to check EVERY clearance there is. Cam to rod, Rod to block, crank throw to main webbing, oil gallery plugs to cam thrust, piston to valve clearance, (use modeling clay and weak valve springs), Thrust clearance, ect. Also on StageII engines you need to verify all the oil holes are drilled, especially behind the #1 cam bearing. If you are running a mechanical roller cam, and externally feeding the rocker shafts, then you don't need to drill the drivers side transfere hole to the lifter gallery. If it isn't drilled and it's assembled, just run a transfere line at the back of the block. If it ran before with no issues, then disregard the oiling hole issues. When using a green(virgin) StageII on-center block there is more than meets the eye on prep work.