[rotorwrench]

Modifications can certainly muddy the water sometimes. Did the growing sample of oil on the dip stick have a heavy odor of fuel? Growing oil level could also be coolant or condense since it doesn't evaporate as readily as fuel does. If there is condense or coolant in there then you will notice it the next time you pull the drain plug. It will be the first thing to come out. It's rare that that much fuel would leak down into the sump. The carburetor float bowl is just not all that large a volume.