SO MANY places could need work on your engines to get it sorted out. It is not terribly hard to do but it seems to be too confusing for a lot of novice
electricians. You may or may not need new panels
. You may or may not need new sensors on the engines. Both engines should be wired the same I would think but may be there was a reason they are not. Hiring a competent tech will not be cheap
but I would not ask any one who has not done this before to do it. For one thing, gas engines require better wiring than diesel
as you do not want any sparks in the engine
room - ever. So you need to make sure that any devices you install are rated for gas engines. Normally you would not be doing anything that would spark but it depends on what you are doing - exhaust
fans being the prime example.
Without actually seeing and evaluating your particular situation no one will be able to give you any detailed advice. I have completely rewired gas engines before. It takes a lot of work and you have to have a basic understanding of electrical
work and common practices for engines and panels
and wiring harnesses. The backs of panels just blow away novice
DIY people most of the time. They really are not that complicated but there are a lot of wires for grounds, lights, sensor leads, starting and ignition. Two stations doubles the work if you need to do anything with the panels (or not). But you really need to look at the engines as each being separate from the other (except the "ignition on" may be shared but the start cannot be shared). And with dual panels you will need to make sure you have the right engine senders/sensors/gauges for oil
pressure, temperature, etc. as they are different for dual stations than for single
Check around with other boat owners in your marina for advice on good boatyards
and technicians. I suggest only hiring someone who has two or more solid recommendations.
You may want to start out by googling boat wire panel circuits and get a feel for how they are done. And there are some good marine
too. Good luck.