the motor is going to be the least of your issues.
how is the transom and stringers?
as for the motor, look in salvage yards for a motor to rebuild. and rebuild it. talk to your local engine builder. you are looking for a 1962-1980 chevy 250 with separate head/intake.
Ted, most battery isolators are just big shottky diodes. should be a 0.7 volt drop across them. the 2 alternator, 3 battery may have additional diodes so the batteries may see 1.4 volt drop (I would have to dig up the specs)
are you running an Acro or Shur Power?
I remember there being...
All SBC oil pans for a 1-piece RMS will fit. However that could be anywhere between 4 and 16 quarts.
What part number did you pull off, and what part number did you install?
Just because it fit may not make it the correct pan for the application
8000hp motors are acceptable
It has to do with the load path. An I/O or IB is pushing the boat from low on the transom. Basically you cant put enough power to tear the transom off with an I/O or IB unless the transom is rotten
An outboard is trying to pry the transom off the boat, and will...
Read links 14, 15, and 18 in their entirety.... All your answers are in the stickies
https://forums.iboats.com/threads/how-tos-and-other-great-information.283508/
I would order some wire, fuse holders and metripak connectors and make new runs or 2 of the cables and bypass the questionable wiring
You could be dealing with a damaged run (cross-talk), corrosion or other
Great Lakes skipper is surplus house that just gets OEM overflow and close outs when a model year changes and sells. If they don't have stock, they won't be replenishing stock.