I've been thinking about buying this 521 for awhile.

[Loren O]

It's oficially mine,bought it yesterday. The previous owner gave me a bedliner,a canopy,& the bumperettes(no brackets though,gotta find those).

[4perrev]

Nice save. Going to need some good work on her though. Swapping beds is not too hard if all 8 bolts come right out, otherwise it could get painful. Here's my bed off:

 

 

[DanielC]

Clean any rust and dirt off the exposed end of the bolts you can.  Home depot sells 2, 3, and 4 inch wire wheels witha 1/4 shank that go in an electric drill, that work nicely for this.

Put penetrating oil on the bed bolts,and wait.   A day or more, if possible.  Put penetrating oil on them again.

Try to remove the nuts.

if the nut turns a few turns, and gets tight again, try to get penetrating oil above the nut, and tighten it up again. 

More wire wheel on exposed threads, more penetrating oil.

Try again to remove the nut.

 

This may seem like a big long hassle, but it still is easier than replacing broken bolts.

[erichwaslike]

Clean any rust and dirt off the exposed end of the bolts you can.  Home depot sells 2, 3, and 4 inch wire wheels witha 1/4 shank that go in an electric drill, that work nicely for this.

Put penetrating oil on the bed bolts,and wait.   A day or more, if possible.  Put penetrating oil on them again.

Try to remove the nuts.

if the nut turns a few turns, and gets tight again, try to get penetrating oil above the nut, and tighten it up again. 

More wire wheel on exposed threads, more penetrating oil.

Try again to remove the nut.

 

This may seem like a big long hassle, but it still is easier than replacing broken bolts.

 

no its not, just go buy 8 new bolts nuts and washers.... itll cost you maybe 10-15 bucks. if they break when you take em of replace em.... id replace them all if you have to replace any.... it can be done in an afternoon, the bove mentioned is a 2-3 day process.... why waste that much time on 8 bolts...... having factory bolts isnt gonna make or break the truck

[4perrev]

Not sure how to get a wire wheel or may be a brush in some of those small spaces, but I've Dremeled of bolts before when they didn't come off. makes muy sparks, so get rid of your gas cans :crying: !

[DanielC]

It had been my experience when working on a 40 year old vehicle, there is probably something else you can do while waiting for penetrating oil to soak in on some bolts.

 

Or you could spend time and money driving around, buying a new bolts.

[wayno]

I have found a great way to get them bolts off fast, if they are rusty your going to replace them anyway, stick a 6 point wrench on the top to keep them from turning, then tighten them with a 6 point socket and breaker bar until they break off, it's a whole lot faster and easier, I do this everytime if they don't just loosen and come/spin off.

These bolts holding the box on are not anything special, and are not connected to any part of the box permanently.