Lucky-R

hello all, if you can offer some info i would be in deep gratitude. searching has offered me only sketches of info so i want to be direct here...

my bro just picked up a motorless 98 civic and we slapped togther a 99 Si b16 block with the 95 gsr head to run until we can put together an itr motor we have planned. anyway, the current engine harness that the civic came with once ran an LS/VTEC swap. sad to admit, the modified harness wasnt done cleanly, and after plugging everything together, the motor idles at about 3K rpms without ever dropping. the motor seems drive run fine despite the idle until we open it up and the car dies out in high rpms. we swapped out new spark plugs, cap and rotor, adjusted the fitv(helped a little with high idle).

basically the dash harness is also a mess, with wires hanging all over the place like spaghetti. the previous owner said he used the ac, cluster harness from a 99 Si, and "left the rest of the wires stock".

here's my dilemma. my other buddy is offering to give me a complete 99 Si engine harness, uncut. i know the plugs wont match with our current set-up. would it be a cleaner install for all wires if i just purchased a complete full unmolested 99 Si dash harness and picked up that 99 Si engine harness from my friend? i'm thinking that would help with all the confusion with our existing wiring in the engine bay and under the dash, and hopefully help the motor run smoother than it is now.

any help or advice to check for would be appreciated also in regards to the high idle and engine shutting of at WOT. thanks all