can anyone tell me how to do or where to find some kind of direction on connecting a s5 turbo engine harness to a 85 gsl-se dash harness?

 

Too complicated! Dont bother trying it.

 

There is no reason or purpose for connecting the two harness'.
Obviously you either havent researched the swap or have no idea how the wiring for the FC engines are laid out.

If you are serious about swapping an S5 engine,then read up.Ive posted many,many times about the needed wiring for 2nd gen engine swaps.It comes down to 3 basic areas........

1.....The big right side harness.....plugs directly from the engine to the S5 ECU.
2......The left side harness.....make from scratch,about 10-15 wires to the ECU from the coils,main relay and fuel pump relay/resistor.There are also a few wires that will run from a 2nd gen underhood fuse block and main relay,to the big right side harness.
3......The 1st gen gauges.....just plug in the stock 1st gen wires for the oil pressure and temp gauges,into the engine sending units.The temp sending units are different between the years,but its easy to adapt.The oil and temp gauges are the only ones that are affected by an engine swap.Same goes for the alternator.

Bottom line,there is absolutely no reason to hack,splice or cut into the 1st gen wiring to make a 2nd gen engine run.Ive run both S4 and S5 TII engines in my 84GS,both of which were CA smog legal.The S5 setup has been running for almost 7 years and 50K miles.