It depends. Do your solid brake lines go all the way to the caliper, or are there flex lines from the caliper to the hard line? If the hard line goes to the caliper, it may be difficult to get it off. You need to use a wrench to get the brass fitting off the caliper, NO pliers or any other tool that can deform the soft brass fitting.

You also need a suitable container and 1/4 inch clear line to drain the brake fluid. Use the bleeder nipples for this. Any brake fluid that gets on the car needs to be wiped up because it will mess with the paint.

Jack stands are OK. Just do one rear wheel at a time.

My old cars are so rusty and I have yet not been able to remove the brass fitting from any of my calipers - so I shop this job out.
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My back feels better when I sit in a Volvo seat

It is not difficult, just awkward and time consuming. Replacing brakes lines is not a lot of fun. Even less if you have to crawl under the car. Not being a fan of jack stands, solid wooden blocks make me feel a lot better when I could be getting squished.

First thing to do is check to see if the bleeder screws break off. If they do you will need a caliper for each broken screw. If the bleeders don't still have the rubber caps you can try squirting a little penetrating fluid in each bleeder before you break them off. It won't hurt to spray a little on the brake line joints. Use flare nut wrenches on the flare nuts. If the bleeders open, there are only two joints for the replacement line.

Greg