In put on new mobile set up with puck,spring,fighting stix giving 12in. of adjustment,102 whip.

Setting up new antenna on 2009 crew cab ram pick up.
1. Can not mount on top of cab.
2. Have tool box back of cab, if I mount to top of tool box whip antenna will be 1 foot from back of cab, and bottom of antenna to top of cab would be 18in.
Q. Do you think it best to mount here or side of tool box? ( I know I want the most metal UNDER the antenna, and not to the side ).
Q. Would it be best to mount antenna to the middle, back of tool box (24in. from cab) with bed of truck 24in. below?
3....

In put on new mobile set up with puck,spring,fighting stix giving 12in. of adjustment,102 whip.