[Jacob Harkins] “so the footage is HD quality”
The footage was HD quality.
The best way to do this is with hardware. The AJA Kona 3 can do a good job and it will just take the center of the image so it will be 16:9 movie on the other end. I do this type of thing with two systems, the SD goes out using the IoHD to my Kona3 card which is doing the up converting. If the footage is not super sharp it falls apart pretty quickly.
The client should be aware that they will not have HD/BluRay quality, they will have up converted SD, unless they go back to the original footage.
This is an example of why HD should be edited as HD even if the use today is going to be SD.