I'm a big believer in JOHN JOWDY's coaching methods.
If you can get hold of a copy of his "Bowling Execution", try to get a copy.
Try the OVER / UNDER on your ball swing plane.
Support the ball with your RIGHT hand.
As you take your first step, (in a 4 step) raise the ball UP and OUT (4 to 6 inches), like your placing it over a steel bar that is in front of you.
Keep your 1st step SHORT, your 2nd step a bit LONGER, your 3rd step is your POWER step, which should be SHORTER again. Keeping your 2nd step LONGER, will allow you to take a SHORTER 3rd step, which will facilitate getting down and into your slide with a good knee bend. A shorter 3rd step can eliminate "rearing up" at the line. Ball should roll onto the lane like a plane landing.
The UNDER part of this is: Imagine that you are trying to roll the ball UNDER a bar that is parallel to the FOUL LINE, about 12" up from the lane.
To generate power and leverage your thumb release point should be behind the toe. Thumb should clear the ball it is slightly behind the shoulder joint, just before it reaches the ankle area.
Thrust from the 3rd POWER step (if properly executed), which propels the body forward, will keep your hand behind the ankle joint, which will allow for a powerful release.
Also, your slide toe does not point at your target. Try to keep your heel and toe in a straight line pointing at your target.
Draw a line from your breakpoint to your target and lock onto it. Imagine rolling the ball along that path. Looks like you are raising your eyes and looking at the pocket early.
Hope some of this helps....a lot of JOWDYISM.
--------------------
Duke Harding
++++++++++++++++++++++++++++++++++++++++++++
I'd Rather be Lucky than Good.