It didnt come from the factory this way

[472viper]

Gap between seat and window crank panel. Sizable gap. Thing is it same on both sides what's up ?

 

[horse sence]

Looks like when the seat was recovered it sucked the sides in a bit ,you may be able to shim the side panels out at the bottom enough to close it up

 

[472viper]

"shim the side panels out..." great idea !