Happy Thanksgiving Mel! Sling points are in front the engine for the stern and a foot or two in front of the steering wheel for the bow strap.
If you are sliding the boat off the trailer to block it is completely different. Use cement blocks for your height and plywood between boat and blocks. Final position on flat, level ground for your blocks should be at your transom corners and your bow keel.
Hope this helps
Roger
__________________
|