finally got a bracket

[phester]

had some spare time today and started to see were this bracket will mount up properly. I simply clamped the motor to bracket, put the bracket in the down position, set the motor/skeg on a floor jack and just jacked 'er up so the cav. plate is level [+ - 1/2 inch] with bottom of hull/transom. Then I started to wonder which of the TWO cav. plates should I align up to. I know that given the shaft length it should be the cav. plate that is measuring down 20" off the clamps. My motor is a '95 or '96 [J8RLEOD] Johnson 20" shaft, 8 hp. Measuring down from the clamps, it's about 20" to the first cav. plate, then 3 1/2" -4" below that there is another identical plate, just above the prop, and it has an exhaust port on it. My question is can I line up the lower cav. plate? [approx 23-24"] the prop and exhaust port will still be almost a foot under water, or do I HAVE put it the 20"? If I could go to the 24" mark, I get to raise the motor and bracket 3 1/2' to 4" higher and, well, that just works better for me.Anybody got any ideas/suggestions? Thanks fellas.