ok so we have finally got the parts and fixed these side speakers up. (if this didnt work we have a set of SEGA RALLY speakers spare which are different so we really wanted to restore/use these if possible.)

So anyone with a BLAST CITY cabinet will be familiar with these speakers, from what you can find online these speakers are over 20+ years old and obviously finding them NOS is impossible and Ive only seen them once a while back in USA for like $100+ years per speaker (obviously need 4). Also the original company no longer make these so its a bit of a mission. Now people have used various LCD tv speakers and wedged them in and fitted them in some kind of format. Basically the rubber seems to perish and there is no fixing.

So while looking into how to restore these speakers I found a guide
printables which was an idea to clean the exisitng speakers and then redo the rubber surround. The guide even gave you the STL to make a mould. So this is where we started.

We had left this a while and asked a friend who was into audio and about if this would work and with what kind of results.
But thats when I found a guide here from
@Spanky UKVAC on a speakers on aliexpress which where the same width but slightly shorter and he had glued a blanking plate into the gap and seemed to do the job.

This gave me a start and I ordered these speakers for around £20, on the original speakers there is a black plate surround which allows you to screw the speakers into the black plastic surround. On Spanky guide, he had screwed new holes and then used a blanking plate, but as I always like to restore parts as original as I can and also in the hope one day the original parts come available I like to make sure I dont damage any original parts. So I got fusion360 and a ruler and started to CAD.
After a while I had a new plate to fit the current speaker, we then added the blanking plate to the plate. We then made hole where the original screw holes would line up and for the 2 new holes to hold the speaker we used pins to hold them in place. So after a few test prints also adding a SEGA logo (which we scrapped), we came up with a working plate which used existing holes to hold speaker.

As you can see on the finished image, it looks all ok and if I ever found originals then can always put them in and I haven't damaged the original mounting case.

So that now just has to be repeated again and the speakers are completed and can be mounted back onto the side panels.
Next up we will look to restore the dashboard.