L&M

Check the different cylinder mounting instructions here. Esp. the Mercury types, you might find it's basically the same as your Tohatsu https://support.garmin.com/en-US/?partNumber=101-7000-00&tab=manuals

The compass/ball can be mounted anyplace that it is free of any magnetic interference regardless of line of sight & yes it will operate if you don't have the throttle actuator hooked up.

Mercury # 866340Q03 Wix equivalent # 51069 or NAPA/Wix # 1069 AC Delco # PF-25 long version or PF454 short version *Mercury, Wix & NAPA #'s will work with either short (remote filter ) or Long ( filter in stock location )

https://octopusdrives.com/products/type-s-t-dashboard-drives/ pm me if I can answer any questions for you

OEM OMC

Yes. The bottom picture in Broke Off's post shows the clutch spring that over time locks to the plastic spindle causing the hard steer.

That is where they go, if you do happen to switch them it will just steer in reverse & you can always just switch them on the computer

There is no need to scrap an X-5 system because of the failed head unit. You can replace it with an octopus drive with few wiring modifications.

They make an external antenna but at 70 or 80 bucks it puts a reasonably priced camera up to the next level altho they say with the adapter it should be compatible with other cameras https://www.spypoint.com/en/products/long-range-cellular-antenna/product-ca-01.html

ck your pm's zinger Is it the older hub/crankshaft style or flywheel plate?

ck your pm's and call me in the morning. I have several.

It looks like electrolysis. Do you or have you left it in the water near any other boats or shore power?

Your right on with #6 for the drive Lost, but his early 3.7L/185hp I'm pretty sure is manual #8. It covers most of the different variations of the 3.7's of that vintage. Depending on serial# manual #3 might touch on it too but not as detailed as 8 **

You have a pm

Pretty vague engine description ( 2br-4bl-edelbrock-rochester) for anyone to give any kind of sound advice, but before I went spending money on dead ends I would check the fuel delivery hose from the tank to the water seperator & any other rubber fuel hoses for internal collapse. Seeing a lot of that in the past few years due to fuel quality/ethanol, if not save a few dollars before you start throwing parts at it & have it looked at by a repuital mechanic.