Just took some measurements from my 73 Electra Hardtop Sedan and the measuremants are fairly close to what you need. Bolt holes are about 54-1/2" across. Bolt holes are 3-1/4" apart center to center. The frame sits inside of the bolt holes by 1/2" on each side so the frame edge to edge is about 53-1/2" and tapers in as it goes forward. Frame is open c-channel with the crossmember bolted to the lower portion. I'd say snag one from an Electra sedan and mount it to the trans and just elongate or drill out a new hole. I even know someone who happens to have the exact same car being parted out in NY and isn't going to need the crossmember if you go that route.
ive seen 2 types of the cross members for dual pipes one is similar to hte 75 but has 2 recesses vs one and the other is off the 73 electra that is not tubular.
The floor & trunk pans are perfect, unfortunatly I'm in Vancouver B.C. so shipping across the border all the way to the east cost would cost a fortune!
Mine is Tubular you can see in the pics several posts back. I would like to get one that bolts right in, but am contemplating combining the one off the blue parts car with the one from the white car (saw each in half and weld together with two exhaust channels):TU:
I'll have to double check but I'm pretty sure mine looked like your pic. It was an oval tube with the humps compressed. I may be mistaken though.
Might be a day or 2 since we're getting a summers worth of rain in the next couple days and my car's parked outside.
Checked a little bit ago and it's deffinetly the tubular style that I have. Stock unit too. So maybe it's because it came from a certain plant or they changed it at a certain point along the production run o No: Either way it's the right style and length with the bolt hole spacing pretty close to yours. Just need to find one now. Try Skyhawk since he has a 73 hardtop parts car that might have the same crossmember.
were you the person looking for the power trunk button in glove box? i found one with the bracket from a 76 bonneville looks close to buick with the yellow button and the bracket