Firstly, do a search on here as there has been loads written.
Things to consider are:
Steering, brake lines, fuel filler line, radiator relocation, engine bay hoses, etc, etc, etc.
If you have a ramp, all the spacers can be fitted at once, without a ramp, its one side at a time. However, can be difficult due to the body angle (hard to get longer bolts through tight holes in spacers, so may have to have them oversized).
Trust that this helps.
Chris