easy not so much:
the chrome and the rubber front bumper is held to the re-enforcement plate with 6 Philips style large head bolts.
the bolts are usually rusted to the threaded holders on the re-enforcement plate which means they usually strip out trying to replace them.
I ended up cutting mine off with a cutting tool.
so it is easier to take the entire bumper assembly off the front of the car from the chassis rails.
usually you discover all kinds of hidden rust damage to the frame rails sitting behind the bumper brackets. so 4 large bolts to remove the bumper assembly from the car,, and usually 2 small screws attach the bumper sides to the plastic grill underneath the rubber extensions on the fenders. Just be careful to search around the grill to make sure there are no hidden screws or you will snap the grill taking the bumper assembly off.
once the bumper assembly is off the car, throw it on the bench and start working on the screws to release the bumper from the re-enforcement plate.
now you may discover the re-enforcement plate is badly rust damaged as well, and you may also discover previous accident damage.
for example not only was my original re-enforcement plate almost eatten away by rust, but i found out the shape of the plate as completely messed up by a previous front end bump. the new bumper would not fit on the old re-enforcement plate at all. I ended up using hydraulic clamps to bend the plate into shape. Later i gave up and bought a NOS 71 bumper re-enforcement plate of ebay for 150$ and threw my original part out. I then discovered my side plates to attach the assembly to the frame rails were also bent, and i bought re-production Scott drake plates to replace that along with the hardware.
i bought reproduction hardware to replace all the rusted out bolts and threaded holders from AMK products.
the reproduction bumper fit ok. the chrome on it was awful and i noticed it had rust spots that i polished out. Later i got rid of it and traded it for a correct rubber front bumper that i painted to match the body.
the rear bumper you remove starting inside the trunk, on the bottom of the taillight panel will be 4 nuts removing them will allow you to take the bumper off once the bumper is off you can remove the bumper brackets and release the hardware from the chrome bumper for replacement
same issues with the reproduction bumpers, the chrome is awful and you may find rust spots peaking through holes in the chrome dip. you can buff the chrome and get most of the rust pores out with metal polish.
the shape of the reproduction bumpers does not match the originals on the ends.
basically the original bumpers were much thicker and the triple dip chrome thicker and better.
for looks i would use the reproductions then call out to chromers and see if it possible to have your original bumpers acid dipped and re-chromed.
all the reproduction stuff comes from the same place in China and sold to various distributors around the world.
So in short it will be a miracle if it goes smoothy and easy. the cars are 40 years old and unless it sat inside a garage most of its life or was recently taken apart and re-assembled it will take elbow grease to get the job done.
as far as time I know it took me about 8 months to finally stop playing around with these parts, i would work on it make a change not like it, discover alignment issues and futz with it for weeks, then i gave up and started to hunt for NOS parts which dragged things out.
the correct bumper cost me like 400$ if i remember. trying to find an original rubber front bumper that was not dead from cancer was a huge undertaking. ford never intended for these cars and parts to last more then 5 years