This will look like shit and I know exactly why.
I've tried this before, more than a few times and I had to come to terms with the following as I waved my white flag.
Standard definition footage of any kind does not scale kindly to HD either through simple upsizing or any number of super-resolution techniques. It introduces shimmer and shake where the video has been de-interlaced, it provides artificially sharpened edges with no boost to detail in any other areas which further creates a strange and disconnected look to it all and unless you're using the upscaled file as a template for some serious post-processing work such as colour grading and grain addition, it's not gonna look markedly different from simply playing a carefully restored SD version.
The reason I enjoy and support projects such as Harmy's Despecialised Edition is that they are utilising the best publicly available source (the blu-ray) to pull back the various Special Edition enhancements and really focus on providing high quality, high definition versions of what audiences saw in '77, '80 and '83. They're already working with a high resolution master and bringing in high resolution elements from various other sources with a keen eye on keeping the standard definition elements to a minimum.
So I suggest, as much as I wish I could get behind this project, to give up and lend your technical and creative skills to other projects utilising the best sources we have.