do i have to remove.....

[rigger3006]

getting ready to put hooker 5901s on 72 340 duster, no sure what theyre called but the 'braces' from 727 to sides of block are still on there, will these headers work with them still on there or should i remove and leave them off?

 

[Locomotion]

Many people have left the block-to-trans braces off. They probably will interfere, but aren't needed anyway. Plenty of very fast cars without them.

 

[TrailBeast]

getting ready to put hooker 5901s on 72 340 duster, no sure what theyre called but the 'braces' from 727 to sides of block are still on there, will these headers work with them still on there or should i remove and leave them off?

I call them bell housing supports.
It depends on if the headers hit them, and some people have to leave them off.
Not a real good idea for a car with any grunt to it at all.

There might be something aftermarket to support the bell that I'm not aware of.

 

[70aarcuda]

Take them off..put them in a box for another day....

 

[rigger3006]

thanks guys, kind of what i figgered, my 72 demon never had them, just trying to lessen the pain of putting those headers on