This is old news, but worth a reminder as it hasnt been widely
reported here.
I chanced upon this article when i was reading a thread in another
forum about fedex's new 757 frieghters.
Freight specialist FedEx Express has selected a US-based division
of Singapore Technologies Aerospace (ST Aero) to convert 87 Boeing
757-200 passenger aircraft to freighters.
............
The conversions will be performed by ST Mobile Aerospace
Engineering located in Mobile, Alabama. Aircraft will be fitted
with a side cargo door, have their main deck floor strengthened,
and be fitted with cargo-loading systems
wow, ST aero is pretty big... i swore i didnt know. 
Source