I'm currently in the process of doing the EL inlet manifold conversion to my EB XR6 I want to know if i can still run my old engine harness if not do i have to run the EL harness, also do i have to run the EL ECU because most of the things i've read about this converstion didn't go into this much depth.

my info may not be spot on as i havent done this before, but i believe you do have to run an EL ECU but you dont have to change engine bay harness, just need to add a wire.

to do it "properly" you need to run an EL ECU, and also get the loom, because it contains the vss switch to switch the manifold.

alternatively, you could stick with you current ecu, and use an RPM switch.