99 Air Nautique - Boat Lift Question

I have a 1999 Air Nautique (D-Drive), we have a cradle style boat lift. Actually this exact one http://www.boatliftdistributors.com/specifications/cradlekits.html

The site states this: "Place the rear sling or cradle beam within 2 feet of the transom since that's where most of your weight is. The front sling or cradle beam should be under the keel, not under the slope of the bow. You might want to adjust the cable so that if water gets in your boat it will drain easily" As I'm pretty new to this whole boating thing. I figured out what the transom was but having difficulty understanding where the keel is exactly located on my boat.
I'd like to get some feedback from people with similar boats and lifts as to how long their 2x10 beams are, where exactly they sit underneath their boat and how far apart are each of the vertical 2x10's
As you can see form this picture the back portion of the cradle beams I have determined are too long and need to be cut about 2 feet short. How about the front ones?

[img]http://www.riverraftrace.com/boat2b.jpg[/img]

hornsfan,
I believe they're referring to the sling placement for weight distribution and balance.

DON'T CUT OFF THE CRADLE BEAM! you need support all the way to the transom.

Your slings appear to be positioned about right for your DD

looks fine just the way it it.... don't cut the 2x10's

Well, here's the thing. I've seen a few boat lifts and the 2x10 cradle beams don't go all the way to the transom. As in from a side view if the boat is all the way up you can see the prop.

I thought this made a lot of sense especially since the boat doesnt always go into the lift exactly straight, and if there is an instance where you go in a little crooked then the prop avoids hitting any of the 2x10 if they arent that long. This make sense?

If you are worried about your prop, move the rear guide poles back so they are in about the same position as the prop

agreed dont cut the 2X10s, move the guide poles and dont pull you boat so far in. On my lift i set up the guide poles so that when the back one is even with the gas tank fill im in the far enough. Then i know i am in the position i want and i kill the engine. If you have your bunks too far apart it will be very hard for you to get you boat straight. just play with it, took me about five times of unloading and loading my boat on my lift before i had it pefect.