So finally after the immense help from danial brother, i fired up the engine yesterday to check it and it started on first ignition on start. It was great and stable alhamdulillah. Mechanic and Wiring Electrician were amazed by the engine and praised it.
Tested the shifting mechanism and transmission and its all good.
RPM and Speed meter is working without any kit or alteration to the speedometer.
Installed OBD-2 Links and checked. Found only two error codes which i am sure is because of ground wiring.