88' Isuzu body lift question

I did a 2inch body lift for the front cab of my 88 isuzu pickup with some hockey pucks (yeah I know its not the right way, but I have a bunch of them cuz im a zamboni driver). but I ran into a problem when i looked at the back. There seems to be no way to remove the bolts in the back. How do you put in longer bolts in the back? Is there a way to lift the bed of the truck off? Help!

Thanx in advance