I went about replacing the rear shocks on my '94 s10 blazer (Square body) (98k miles) the other day... what a freakin' nightmare that turned into. Let me preface this by saying... I'm about 99% certain this blazer was in a saltwater flood at some point in it's life. from the rocker's down... the word 'rusty' is being polite.

Using the torch was my last choice since I was working right next to the fuel tank and fuel lines.. but in the end.. .I had to torch both the upper mounts bolts off because they were so heavily corroded a 6pt 13mm socket wouldn't grip them.. and 7/16 or 12mm was too small.
the driver's side was even more fun, because I couldn't see the inboard bolt at all. (the square bodies give you a 2 or 3 inch gap to work in) and the shock was blocking my view.. so I ended up torching the shock itself into several pieces to get it out of my way.
the lower mounts were just as bad. that nut came off easily with an impact gun (solid 21mm nut) I had to heat the bottom of the shock to get the rubber bushing to let go.... this left the innner steel bushing solidly rusted to the bolt.. thankfully it's just a piece of rolled steel with an open seam... I applied lots of heat until it was close to red hot.. grabbed it with a pair of vice grips and rocked it back and forth... and along with some help from a hammer... was able to slide it off. . I wire-wheeled the shafts off.. applied a liberal coating of copper anti-sieze... and then install the new shocks. i used washers on the frame side because I did torch a little bit of the frame too

today... I need to adjust the shift linkage again so I have park... (I disassembled the linkage when I was working on the brake lines) and then the front shocks.. oh boy

 

Semi-pro tip: Old license plates make good heat shields. They are easily cut with tin snips and bend into shape to fit into holes and hold themselves in place.

 

I forgot to mention I did use a piece of heavy gauge steel.. (probably around 12ga) to shield the fuel tank.

 

Dang that sucks but good job getting those shocks replaced.

Rust makes me sad.