I don't know your boat but you should be aware of where the straps are placed.
Try to place them at or near a bulkhead to prevent to much flex on the hull as the weight is applied to those straps. I have seen damage caused by the straps applying to much pressure to things like rails and the deck hinge.
The same when you block the boat. Do you want it bow up level or bow down.
Is it going on a cradle or are you using stands?
IF using stands I like to use 4 per side.
With 4 you can remove and replace them one at a time to do the bottom paint.
If you can't repair it maybe it shouldn't be on the boat