My drives are mounted above the rub rail, and below the engine hatch. Think I need a spacer Clark?? :D :D

I believe to get the actual X dimension, you add 9.25 inches from the measurement below the transom assembly to the bottom.
I know on a single, you measure to the bottom of the V. Not sure if that how you should measure it is well for twins.

No you just need to put some of those fancy lights under your driveslike the ones under your seats!!!:drink:

Trim is the same. I have two sets of props 30 & 32. I use the 30's for topend get a little more out of them, 90mph and the 32's for long distance cruising, get about 5 mph at the same rpm, top end loses a little 87.5 . Cruise at 3000rpm at about 45-46 mph. Fuel mileage 1.5 mpg:drink:

I did try Rich's 1 1/2 inch spacer's, they were great out of the hole shot NO SLIP but lost some cruise and top end. Went back to the 1 inch. I think they work the best.

Drive height/X-dimension
 

Bobby Moore instructed me on drive height/x-dimension...His suggestion was to use a long straight edge on the hull, say a 4' or 6' level and hold it up on the hull; run it straight past the lower unit with the drive in a level or neutral position...measure from that line down to the center of the propshaft. This dimension should be between 4" & 6" for a 75-90 mph deep "v". Step hull could change this number slightly. Just what I was told; maybe this will be helpful....of course the best lessons are the one's learned thru trial & error! LOL

Same way I was told to do.I think mine was 6" from the bottom of pad to center of prop shaft.

I'd be willing to bet that Pat is reading all this and saying Hmmm?????

I bet your right!!!

Well my boat had 1-1/2" spacers when I got it. When I spoke to previous owner and told him I planned to take the spacers out he said"don't even try it" boat was blowing out and once on plane would porpoise out of control. Could be cause it's a twin 28...so I left them in after talking to Bobby Moore...x-dim. is 5.5" right now.