need help on reverse flow smoker build

[ham35]

Hi my name is Tim and am new to the site from Indiana, I currently am building a reverse flow smoker, I do know all of info on the style of smoker the baffle plate the flue opposite end etc..... But my questions is this. When installing the baffle plate is there a particular distance of space you leave open on the opposite end of smoker box? The second question is at the end where smoker box would be located, does the baffle plate get sealed there and is it above smoke box or should there be some sort of opening there? Any help would be gratefully appreciated.