Who knows? I wouldn't know where to begin.
Let's say that even in its present condition I can sell it or trade it in for £500.
And lets say that with a perfectly running engine I might get £1500, but more likely £1000.
A new fuel pressure regulator, fuel distributor with EHA valve, OVP relay, fuel pump, dizzy cap and rotor, could easily swallow up that £500 difference. The EHA alone can cost that.
For someone who wants long-term car it would be worth buying and fixing, but for me, given that I never intended to actually keep it this long maybe I should just cut my losses now and buy the Porsche.
It's a 1990, with the M104.980 engine.