I'd always do a double check, even if you're buying parts from the best engine builder in the world. Stuff happens, maybe the kid on the dock at SCAT puts the balanced rods into a box with a different crankshaft or something like that.

I got a complete rotating assembly once from a highly respected engine builder and when we put it together the crank wouldn't rotate. It turns out the bearing mfg had mistakenly put some +010 bearings into the std bearing box. To make it even worse, the +010 bearings were stamped STD on the back side. Only way we ever figured it out was to take all of the bearings out of the motor and measure each one with a bearing mic.