Has anyone attempted to put a Zongshen 167FMM crank and/or rod in a 169FMM motor which would technically stroke it closer to a 250cc?

I believe the ZS167FMM is 67mm bore, 65 (or 66)mm stroke. The ZS169FMM is a 69mm bore, with only a 62.5mm stroke. Is it the rod length or crank that is different? Thoughts? The 167FMM rods and cranks are pretty cheap, even if it meant doing a bit of valve clearancing it might be fun to try.