Piston orientation is definitely important so its very good you caught it before buttoning it all up. The pin is offset from the thrust side of the piston. We purposely did this on a formula V engine years ago, and it did make a small increase in power, but it knocked badly enough that the sound alone prompted us to not do it again. 2 Stroke engines really do not tolerate this at all, at least 250cc-400cc engines that I've worked with, maybe marine outboards are similar. You could always do a quick leak down test without the intake attached to obtain a baseline leakdown. It should not be above 10-15% on any cylinder even with new, not broken in, rings. After break-in, this value should be 5% or less dependent upon the rings and pistons used. Hope to see her humming in a video soon, nice weather is quickly upon us, and I feel so far behind now.