door alignment issue w blazer

[BIG ORANGE]

Replaced the intire floorboard and firewall with one from a truck cab, took lots of messurements and everything came together just fine, hung the door and have proper gaps around the doors. Now heres my issue, I have to lift the door up to close or open them, after they come off the strikers they drop down around a 1/2 inch or so. I haven't installed the rocker boxes yet therefore I have flexs at the firewall causing the drop.... I'm new to this blazer stuff but having fun figuring it all out. thanks for any help.
Donnie