19x2

[triton19x2]

I just posted about a week ago in another colum a question and thought I could get more repines here.  Anyway I have a 19x2 225 opti.  Running a 8 in backplate and about to add 1 in. Spacers and 4 blade txp prop.   With hopes of getting 75 mph.  Any suggestion on height or set back or props.  And was thinking of a simon job on computer any thoughts ?