Ok, so if everything except the engine/ECU is untouched on the D2 body you should have all the body controll working on it(central door locking, alarm, exterior and interior lights, etc) for the starter you should find the BR wire with lucar connector in the engine bay and as long as the fob works the starter will work as well, to override the immobiliser you'll have to give direct earth to the starter relay's coil at fusebox plug C0573-7-BO, so here's the plan, remember
vehicle-connector number-pin number- wire colour , and when i say "
black plug" means D2-
C0658(engine bay)strangely some colours are mathcing between D1 and D2
)
-cluster earth, all the B wires you find coming out of it connect them to B wires from D2 plugs or direct to body
-cluster feed: D1-C222-2-LG to D2-C0230-19-LG
-cluster illumination: D1-C222-7/9-RN to D2-C0230-12-RN
-speedo: D1-C221-2-BR to D2-C0233-13-RS and the speed transducer signal into black plug pin 6-RS
-tachometer: D1-C207-5-WS run wire to the alternator
-fuel gauge: D1-C221-3-GB to D2-C0230-14-GB , you'll find GB wire at the D2 tank's plug
-coolant temp gauge: D1-C222-8-GU to D2-C0233-15-GU the temp sender signal to black plug pin 7-GU
-oil pressure: D1-C222-5-WN to D2-C0230-6-WN, you shopuld find a WN wire hanging in the engine bay
-direction indicators: D1-C207-4-G to D2 fusebox C0587-12-GR
-hazard: to D2's hazard switch LGR wire connect a relay's coil, other side of coil to live 12V and a 12V through relay's contact to D1-C207-9-LGG
-main beam: D1-C207-3-UW to D2 fusebox C0586-14-US
-handbrake/brake fluid level: D1- C222-3-KO to D2-C0230-10-KO, you should find KO in the engine bay where the brake fluid reservoir was
for the SRS and seatbelt warnings i'll have to think hard cos it's vague in the diagram and these were managed by the D1's MFU which is missing now, be aware that all these connections are based on both vehicle's diagrams and if something is not matching it might be a mistake in the diagram or my mistake so after you conncted wires dont install the cluster untill it's not tested or eventually i missed something... then if something is not OK we'll fix it "in situ" ... Good luck