Okay so I pulled across the homepage images found on RJAY63's link of Wayback Machine.
It's obvious that the "Welcome to Metropolis Street Racer Gomepage." text is also an image, but Wayback Machine didn't have it, so I'll have to rebuild it. And the CHAT menu icon. That being said, this page is nearly complete.
All I have to figure out is the top banneer (With the MSR logo). It was never natively in the code for each webpage, and as each page was saved as .php on the server, I can only assume this was a frame of some kind added to each page - however I'm not sure which type. If I get it wrong, it may not operate on the Dreamcast. It'd also be helpful to know what may be on the left side of the banner, however it's completely concealed in this shot. In the other shot we see small watch and Kudos logos, however I think these were links to switch between leaderboards, and not a general part of the banner design.
In short, rebuilt homepage is 95% complete, with just the Welcome image, Chat image and banner to be applied. Existing pages from Wayback machine have also been salvaged and rebuilt fully, with links operating where pages have been recovered.
Then it'll be on to rebuilding the missing pages. Any information you can find or share about these pages and how they worked would be great. Chat and Message Board are of particular interest, as I'm not sure how they would have operated.