e30ftw

I did a similar repair on mine. That part is borderline impossible to get to without cutting open more of the chassis. The rust starts on this piece underneath and spreads to the cowling area and under the windscreen. Check through the opening the inside of the lower windows in the corner, it usually starts from the inside. Take the fender off and you can slice open the inner fender. Also check the inside through those openings, feel up under the bottom of the windscreen and down (shown where I cut below). Generally the lower windshield corners rust from the inside out.

On the passenger side remove that globebox bracket, it's usually above that where the harness grommet passes through to the fusebox. The floor pan looks clean so that's good.

To get the best repair done you will need to remove the carpet, dash, heaterbox etc to get to the backside of it make sure it hasn't gone all the way through. I'd wire wheel it all and treat it with rust converter or POR15 to seal it. If it's made holes you will need to cut and weld. Check behind the brake booster / fuse box harness grommet and from the inside, drop the glovebox out and look there too.

Pull the sound deadening off the firewall. Prefacelifts are notoriously rusty on the firewalls and down to the footwell on the inside. I can see a hint of it in your photo in the circle cut out next to where the steering column comes out. I'd lift the carpet at the front too.

Different size clutch disc, the flywheel also has the pilot bearing embedded in it instead of the crank, so the input shaft length may be shorter too.

That will only work with an E46 flywheel / clutch / starter.

M54s are cheap. Almost everything is the same swap wise, it's just slightly more wiring involved in the adapter harness and having drive by wire. It's relatively easy and considering the amount of effort of doing a swap and cert etc, a better overall option for a more modern engine and power/torque is more than enough for an e30.

Ohh whoops, yeah got them mixed. I saw the interior picture of the coupe and the wiring looks diced up under the passenger seat.

I think that one's butchered, I've seen him post numerous questions fighting wiring gremlins and not being able to get it started. The whole car was stripped by a previous owner and he put it back together.

Figured as much. I've bought enough e30s over the years and in at least the last 5 years they ALL have rust, its just how much of it.

Odo stopped over 10 years ago at 307,000kms so its probably well over that now. I also doubt it's rust free. Check all the usual spots - Lower A Piller under the Front windshield, Firewall behind the fuse box, under the front battery / battery tray, firewall around the steering column, Front radiator support (usually lower part, between the chassis, or anywhere really), Front sills / lower front guards, rear trunk pockets each side from the inside and underneath them and the rear valance, also around the edges of the bootlid and around the taillights is hard to spot with trims and lights in place. Just take a peak underneath with your phone camera. IMO the good: Paint looks tidy, Leather door cards, manual (but that's really just a pedal box difference, unless its the gearbox you are after too, which would work with an m5x). The bad: high unknown kms, probably needs a lot of underneath unless it's well maintained, Manual windows suck but thats preference, Seats are probably torn to shreds based on interior photos and seat covers, no engine bay pics so hesitant to make a comment on it's overall condition and whether it looks maintained or not. Overpriced by 5k I reckon, and that's if it checked out as rust free and well maintained.

https://m.facebook.com/marketplace/item/1659415685006102/

You won't find a rolling coupe body that easily unless someone is abandoning a project. And if you expect to find one without rust, you're dreaming. They all have rust now. Only exception are mint examples that have been garaged their entire life. If anyone tells you it's rust free it's either been repaired (and you never know how good) or they don't know where to look. Your best bet would be just look out for a 316i/318i coupe and go from there. In the last couple years they have been going for around 7-10k. But definitely expect rust, it's just how much you are willing to deal with.

2.5k upwards.

You're better of going with a 316/318i and m54 swapping it. The price on m20b25s these days is ridiculous. You can pick up an m54 half the price and have a more modern engine with a better power band that is more than enough for an e30.