Best 3/8 fuel pump solution?

If you go to my website, there is a page on mechanical fuel pumps with both factory data and some independent testing I had done (by Ryan Brown). The 6 valve pumps are the best but have fit issues with the US '70 up style water pumps. There's some photos of the fit issues on the same page. Not sure how that will translate to your RH drive and Valiant builds.