Just spent the last month and a half doing through floor sub-frame connectors and sound proofing the floor and tunnel of the car.
The sub-frames were quite the task and took a lot longer to do then I thought it would. I used a 2"x3" .0125 steel tube to make the connectors, one for each side of the car. I cut into the sub-frame channels and clearanced both sides for the bar
I located and cut into the rear frame rail just to discover that they were about 2" off of the front on both sides. This means I needed to custom fabricate a bar for each side. :(
I basically did a Z-bend in both bars to make it line up front to back.
I tack welded each section to test the fit until I knew it was right.
After I got both sides to fit I finished welding them and cut the rest of the floor so I could install them in the car.
I welded both top and bottom and made some re-enforcement brackets for the drivers side seat.
After I welded them in I painted the inside and out with a decent quality rust resistant primer.
I then proceeded to cover the floor with a good quality Butyl rubber sound deadener.
I did double layers in the trouble spots around the trans tunnel.
I also did the door panels.
Thanx for taking the time to read my post, BTW I also installed an aluminum flywheel and CenterForce DF clutch. All the new changes made a huge difference in the cars ride quality and performance!