Did you ever see if car leans when battery is not in trunk at all? I suggest that 1rst.
Could be air pressure. Maybe. Could also be (if car leans without battery in trunk that back right spring is worn more than back left. Yeah, and it could be that you have more stuff on right side (but I seriously doubt that--how much crap would you have in your trunk anyway.)
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'79 Mustang Coup
4" Cowl
Weld wheels (15x6;15x8)
Stock 5.8L
C4 w/ shift kit
1.5" MAC full length headers
Holley 750 CFM
Edelbrock intake
2.5" Off road H-pipe, 2-chamber Flowmasters
8.8" Rear end w/ 3.55 gears (Now that's more like it!!)
Front: 225/60/15 Rear: 255/60/15 Eagle GT II
14 x 4” K&N air filter (getting the Xtreme setup soon)
"Red, thou art my companion. Hasten now your quickened metamorphosis to Green
that I may conquer all who dare abide there beside me. May they be left thither
behind burnt black." ---Fox Body