Level 1: Very Easy
Products with this difficulty level take less than an hour to install. This product typically installs using basic tools (ie hammer, adjustable wrench, electric drill). These products are very easy to install.
  Level 2: Easy
Products with this difficulty level require simple hand tools to install, like a screwdriver, adjustable wrench, and standard power tools. These products typically install using screws or bolts. If you own a screwdriver, you can probably install this product.
  Level 3: Moderate
This product requires mechanical skill. Usually requires removing/installing bolts in hard to reach places. We recommend that you have moderate mechanical ability to install this product.

  Level 4: Advanced
This product is difficult to install and requires someone with greater technical knowledge about the task, or requires specialized tools such as a voltometer, soldering iron, ect
  Level 5: Experts Only
Products with this difficulty level should only be installed by a certified trained mechanic. Do not attempt to install this if you are not an expert mechanic. This product may require welding, grinding, cutting metal or precise measurements.