just put 87 scout together with 2.5 merc it has set back bracket plus manual jack plate .dont know where to set prop shaft on boat any one have this set up and know the dos and donts thanks

Rule of thumb is run it as high as you can get good water pressure....You should post this over at screamandfly...you will get much more responses there.

Good question. Luckily I have a hydraulic jack plate. To be honest, I am still trying to find the sweet spots. I agree with Turbo, ScreamandFly will be your best bet to get some good input.
Jr.

is there anything you can tell me about set ups iveonly had a hydrostream vegas and this bot is so vwdifferent

I would check out the Rigging a 21 superboat thread on S&F... I would think to get the most out of the boat I would go with a hydraulic plate...
Jr.