I solved it by using cannulas. They are made from stainless steel, and solder won’t touch it. They were thin enough to separate the pin from the through-hole. It still was nerve-wracking. That was my main machine I was working on, a nearly prototype Amiga 1000 that had cost me a fortune.
Been there, did that. With a similar iron, I unsoldered am MC68000 CPU (DIL64) from a mainboard. Neither ruining the chip nor the board was an option.
The big tip might be advantageous to desoldering a 64 Pin chip with through hole mounting.
Add lots of soldier wire and a big tip might alow you to apply heat equally so you can pull the chip out.
Still not an easy task, but easier than some tiny microsoldering tip.
I solved it by using cannulas. They are made from stainless steel, and solder won’t touch it. They were thin enough to separate the pin from the through-hole. It still was nerve-wracking. That was my main machine I was working on, a nearly prototype Amiga 1000 that had cost me a fortune.