I was finally able to get the fuse box apart. There are some clips on
the inside that you have to push a screw driver into to release them. I
had been trying to do that, but had not found the right ones to push
on. After two hours trying to get the box apart and finally finding the
right two places to release it....I had the old link out, new one in,
and box back together in less than 10 minutes. Then the new battery in
in another 5 minutes and the truck running again. The only other
problem was a blow radio fuse. Once that was replaced all was working
again. The 80 amp fusible link was $2.99 at Auto Zone. Nissan parts
department wanted $14.00, go figure!
BTW, I got the battery at Walmart and had to take the first one back
because the side terminals stuck out and top positive terminal was too
far back. The battery book recommended either of two batteries. Of
course I got the one that didn't fit first. The other one didn't have
side terminals and it fit perfectly. I can't remember the numbers, just
get the one with no side terminals and you will be fine.