Good progress was made tonight.
Annoying rattle and wobbly engine was traced to a rear engine mount bolt that was tight in the hole but not actually tight against the mount. That was sorted.
Oil pressure problem was tackled. Pressure relief valve was cleaned out. Pressure sender also cleaned and rewired.
Finally, the 1.8 distributer with Hall sensor was fitted in place of the ECU controlled distributer and coil. Only three wiring connections were needed. Live feed from the original coil live. The ECU coil earth was cut and the ignition module switched earth used in it's place. Finally, the new circuit required an earth wire. After sorting that, the engine was started and it fired into life first time.
Which was nice.
We then divved about with the timing a bit.
First test drive has shown that it works fine, you wouldn't notice any difference between that and the ECU driven coil.
The Kent cam kit should be arriving soon. I've got a set of new lifters ready to go in too.
So, all I need now is some carbuncles.