The Lowrance cable steer autopilot is about $1500 and would work with the existing steering but you would need specific Lowrance units such as the HDS gen 2 or greater to operate it.
I have the same boat. I put on a 9.9 Suzuki EFI for added safety and lower fuel consumption. Added a dedicated hydraulic steering system just for the 9.9. I also had a Lowrance hydraulic outboard autopilot system which integrated directly into my HDS12 Lowrance. I am surprised how well it works. The extra helm for the dedicated system is installed next to the cabin door and has a small crank handle to turn the 9.9 when not using the autopilot. This is very useful to me when the water is low in my area as I can trim the I/O up completely and use the 9.9 to get to my dock. Attached is a picture showing the fuel tank on the ladder. I have since attached the fuel line directly to the extra port on the Mercruiser filter on the 4.3 with no adverse effects. Lowrance also has an autopilot that attaches behind the helm and therefore would keep the stoch steering in tact. I can't comment on its effectiveness but I know it exists.
I currently have a 4.3 Mercruiser which has 5 drain plugs. Pull them out one at a time and blow compressed air into the drain plug thread area. A hose with a rubber cone for good sealing against the hole in the block and a valve upstream does the trick. A few blasts in each hole and you will be amazed what comes out. I run in a muddy area on Sandy Pond and it sucks up a lot of mud especially late in the season. Been doing it this way for over 40 years with no problems. Had friends that just pulled the plugs or didn't do the antifreeze properly and had cracked blocks.
Go to WalMart and get 50 lb Shakespeare. It is quite large in dia so the fleas cannot grab it. It is also very inexpensive. Put on about 200 ft, this is enough to cover your vertical member from the down riggers. Put on about 20 ft or so of 25 lb test leader to cover the distance behind the ball. Problem solved. Pay attention to knots so you don't have a problem thru the rod eyes and level wind on the reel. Has been working for me for many years.
Used to fish Park De La Verendrye in Quebec once or twice a year until my father passed away. Had many good trips there. Drivable and loaded with lakes for pike and walleye.
Was planning on a walleye trip to Oneida tomorrow. Once again trailer lights not working. Chewed in inaccessible places. Happens almost every year because trailer is stored outside. Any preventative suggestions when rewiring would be appreciated.
I will be out of town for about two weeks. I will take 6 or so if u have them. Maybe a few in blue also. Please put them on the side until I am available. Thank You.
I would b interested in this one. Black back, orange belly. Live in Wilkes Barre area so I can arrange to meet. I have bought from u before. Met in Moscow area