There are a variety of options.
FFMETAL has a kit which allows you to place it in the trunk under the trunk aluminum.
Advantage of trunk location is weight over the rear wheels. Helps with traction
Breeze has a kit which allows you to place it over the passenger foot box. Advantage much shorter cables.
In short it's your car. Others have done as above more cost effective.
Some mount them on the X frame in front of the engine. Here's a pic of mine under the aluminum. This is IRS, if you use the straight axel, it's get mounted just to the left of the pumkin. They all have their advantages/disadvantages.
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