Personally, I keep my diffs as loose as I can get them without seeing diff slip. It does seem like having loose (but not slipping) front diff and tight rear diff can cause oversteer/s#^thooks. Beyond slipping or non-slipping, I measure diff tightness by grabbing one wheel and the spur, then trying to turn the other wheel. I 'measure' with my hand how much torque it takes to slip the diff.
A diff that is tighter than it needs to be takes away traction from that axle during a turn.
Having the front diff slip on corner exit will make the car pretty much impossible to drive, as the car ends up in rear-wheel-drive, which leads to huge oversteer on corner exit in our touring cars. [fronts have full traction available for causing cornering, while rears have almost none and so break loose instead of supporting cornering].
brew, you are flat out smoking your diffs. If I were you, I would pull apart both diffs and sand the thrust washers until the ball tracks disappear, then reassemble and follow the instructions. Page 7 of the 007 manual has the diff setup procedure.