I'm updating this thread for future search purposes. I put the 5" aalcans on. The stock shocks were indeed 2" too short even at the extended length. I had to hook my 5k lb trailer up and put about 500lb in the bed and have someone jump up and down in the bed to slip the shocks on.
The ride was the harshest I have ever seen. My aalcans are very stiff and so basically I had no uptravel or downtravel. Every bump was like bottoming out. It was ok to go down the rode to the store. (I had already ordered new shocks of the correct length from downsouth motorsports
I would not suggest doing this in any bad weather as the tires leave the ground with every bump. It would be dangerous. Definitely this is not a setup to have for any amount of time or to use for daily driving. Perhaps I will measure the old shocks and put the measurements up here for others reference.