67 C10 new bed floor not lining up mside to side

[vikingsandpintos]

I am helping my daughter with her 67 C10. She is converting it from a long bed to short bed. We got the kit from Brothers Truck Parts, to shorten the frame.

We got that done. We couldn't find a decent used short bed, so we bought all the parts from NPD to put one together.

We set the floor on the frame, to see how it fit. We lined it up with the frame holes and brackets, and dropped the bolts thru the floor. But the whole floor is about 3/4" too far to the right!

I measured from the back of the cab to the rear bumper, measures the same on both sides. Didn't have any issues doing the frame plates when we cut and shortened the frame. Pulled the bolts back out of the floor, and did some shifting around with the floor. I got it where it looks like it should be, same gaps between cab and floor, and floor and bumper, on both sides. The floor is shifted 3/4" to the left, to center it correctly, measuring off the frame on each side to verify it is centered.

The bolts now don't go thru the frame and brackets. It looks like I will have to elongate the holes, and at that I'm not sure there is enough material to make a big enough hole. I can weld some plates or half washers, ect, to widen the mounts enough for holes, as that looks like my only option to be able to center the bed.

Has anyone else had an issue with aftermarket floors being off that much? I'm not sure what else it could be, other than the floor itself having the holes made off slightly. Just seeing if anyone else has had this problem? Thanks1