Do you prefer AC Delco plugs?, they work fine, oem number.
Remember to keep spark plug socket STRAIGHT on the plug coming out and use finger tight going in, then torque with socket as required snug, if rusted tight, a little break free penetrating oil a few times like B.K. mentioned has done the trick for me when stuck too.
Tagged each wire just in case before hand, wrote cylinder number on plugs coming out and saved them to compare to previous plugs to monitor engine condition.
In the past when I could do stuff, on occasion, used some cardboard or blanket etc. for comfort while laying over fender, and taking time to do it right, a couple of different length extensions, not being in a hurry.
Also, checked gap on all plugs before install to have everything ready and maybe a tray or magnetic tray that is easy to reach when hands are down by plugs, easier to replace one wire at a time, mark cylinder number on outside of distributor cap if you want, just some thoughts.
Depending on physical condition, stretching your muscles and body for a while helps for reaching down and wrenching in the engine bay.
