All cars including used have gone up in price considerably since then. I am seeing 10 year old work trucks selling for more than their original sales price. I bought my FB in 2019 for $2000. Needed some work to get the engine going (fuel pump, carb rebuild) but interior and exterior are nearly perfect. Now try to find me that today! A junkyard near me is selling a non running FB with visible rust and a shitty interior for more than I paid.
I tried to do some detective work for you but I couldn't come up with a name, just where this pic has been hosted without much detail.
I did manage to find a tumblr page that has a heap of RX7 photos listed, and this FC features a few times. I have no fuckin' idea how tumblr works, but I couldn't access any of the notes (I assume they're like comments?) but you can access them then maybe there's a discussion on one of the photos about what kit it is.
Idemitsu Premix Oil?
If he does his own oil changes, maybe a few Mazda oil filters?
You need the manifold for it, but yeah. Carb -> upper manifold -> lower manifold (stock on my car) -> engine.
There is a random one. IDA's are a bit more popular, but DCOEs have a choke and mount further away from the exhaust, and have a longer intake. All of which I like.
If the dimmer circuit positive passes through the dimmer pot first, then you can just use chassis ground for the illumination. I'm not familiar with the cluster wiring on the FB/SA though. The FD has source voltage at the bulb positives, and the grounds run through the dimmer, then to chassis ground (the opposite of what you're describing).
You can determine wire size based on the current draw of your device and the wire length. Your factory wire gauge should support that cluster just fine. I ran 20 AWG supply wire to my ECUmaster ADU7 dash since it barely draws over an amp and it was a short run from the "meter" fuse under the dash. The ground had to be 18AWG. It passes the same amount of current as the supply wire, but it's a longer run (it grounds to the engine block).
The best way to splice multiple wires together is the brass TE open barrel splices (you can get them on ProwireUSA towards the bottom of this page). Keep in mind they require a special set of ratcheting crimpers that are about $100. If you don't do this very often, you can use some weather tight splices here, just do a couple of test splices and make sure they'll hold up before doing them on the car. Check out Prowire USA for quality wire. I use lots of TXL wire from them and it's really nice for the money.
Also, check out the "Motorsports Wiring Alliance" page on Facebook and High Performance Academy for more wiring info.
If you can’t source wheel spacers I’m not sure I want to share roads with you. Obviously assuming you have stock hubs and are correct about the amount of spacer that will prevent rub, (which is not necessarily a safe assumption because you aren’t including tire specs) you just need 7mm wheel spacers that are 5x114.3 and the correct center bore(67.1)
Here’s the listing, it’s got a glass sunroof but I think it was swapped of a GSL-SE. And I think the seats were swapped so it may have had leather at one point.
I bought a pack of these 9 4oz bottles. I could do without the dispensing cap, but it works great when you are at the gas station.
buy this book and read. Lots of good info in it. Also get a manual from foxed.ca for your year car. 84-85 the same.
The MA02B is for 1990 and up vehicles.
The MA01B is for 1982-1990 vehicles.
Being that you have a 1988, I think it's pretty clear that there is a harness made for your car.
As far as the stock amplifiers go, follow /u/jlee89's suggestion and bypass them but use the stock wiring. It's simpler that way.
50 bucks and some time to hookup the cables...