Frankly I like to be UNDER them. Let the MK1 eyeball guide me. Far more accurate than any radar or strike finder on the market. Not always practical of course....but it's the best level when encountering a line of CBs.
Exactly........ the lower the better.
Back before the days of GPS I was ferrying a PBY over the ocean and ran into a situation where I had to get through such a front and at the time I was flying in T effect for lower fuel burn to extend my range and found that staying at one hundred feet allowed me to pick my way through the heavier rain due to being below the cloud and also the vertical air currents get flattened out at the surface and the up and down movement of the airplane is cushioned by the descending air bursts being flattened out at the surface.