Have a 2002 SR5. Bought the Toytec Boss coilovers last year. Went for the 550 lb Eibach coils for the "smooth" hwell: ride. I was not thinking steel bumper at the time.
My question is will the 550 lb rated coils do OK with the added weight?
I put 700 lbs springs on my kings setup with CBI, and winch. Feels nice and smooth. I don't think anything less would work, but a lot has to do with the speed. I like to go fast on unmaintained road.
The easiest, and safest, way is to use a spring compressor set. AutoZone probably has that tool in their free loaner program. Or you can head to Harbor Freight and buy the MacPherson Kit for $16.
Not hard, just a little time consuming. You're local auto parts store will loan you the tool, you have to pay a fee but it gets returned once the tool is returned.
Just go slow and be careful...no problem at all.
You didn't say if you are running a winch or not....the bumper alone isn't bad.