I've had the same fight on my 54 car a few times. I always have to try a few different ways to slither it in place before I find the magic way. It has several tabs and such to catch it when it's 'almost there'.
You should not have to force anything (unless something was bent in the process that is).
One thing that helps me is to NOT put any screws in until all holes line up. I use those small wooden skewers to poke thru the holes to tell when the holes are aligned.
Good Luck!!!
