The rocker you have looks longer than the one on my floor pan. I have replaced the whole door frame . but there is a second hole in the rocker that looks like it should go behind the door post on the front. but when i align that up it wants to close my 33.5" gap .
Thanks,
Buck.
Can you post a picture of your rocker? Mine does not have any holes other than the 3 in front of the front door post for the parking brake support bracket.
I would position the rocker and door post to maintain the gap.
There's a dimension in the Factory Assembly Manual (Section 1, Sheet 1.07) that shows the front end of the rocker positioned 8.47 inches behind the face of the firewall.