Presume you drivers tubes enter door. Remove the triple thick metal inside of door from top rear of door to vent window similar to the site picture you posted. Don't remember, one side or both drivers side and passenger side weigh 9 pounds IIRC. Cut drivers side out, weigh it and make a decision for passengers side.
Upon decision ^, cut "X" tubes out of passenger side of car, install "X" NASCAR tubes similar to Speed Engineers new car . Cut out door sheet metal and triple thick metal same as drivers side door.
If you can implement a harness tube from the main hoop diagonal to the main hoop drivers side to attach harness to remove horizontal between main hoop rearward diagonals.
Remove inside door handles and operating rods and replace with 1/16 inch steel cable.
Remove all PIA crack seal which is squeezed out in people compartment floor and trunk.
What is the weight of the aluminum plate at drivers feet? Remove plate and install aluminized heat barrier matt to underside of floor, tunnel and angled firewall. Did it to my car and a couple other cars with zero heat issues.
Black sheet metal and bolts in passenger foot well.
Does the big ol RPM tack have value? Is the center column shift light be connected to the OEM tack or could it be connected to the OEM tack? If so get rid of the big ol tack.
Looks like the drivers side window net as attachment rounds top and bottom. Legally the window net shall open from the top. If the lower attaching round is steel, replace with aluminum which is 1/3rd the weight of steel. Whatever the upper attaching round is, could you replace it with aluminum?
If not using OEM tow loops remove them.
Remove cable inside trunk to open gas fill door and replace with ty-wrap. Open trunk, pull ty-wrap to open gas fill door.
YES, many of these items are PIA items, but weight is weight and you only do them once and you HAVE weight savings.
Please remember, Have Fun.
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