Replacing the wiring is exactly what I have I mind. There is very little wiring in there so I think I will be good to go doing this on my own! I am inquiring about those packard connectors only because the wires were so brittle that they snapped off at the connection when I tried to undo the connectors
If you want to remain completely compatible with the c.1972 methods, I suppose you will have to find a source for the connectors that were used. However, if you don't feel the need to remain backward-compatible with 1972, you can select more modern connectors. The present day BRP engines tend to use more modern connectors like the DEUTSCH connector, also made by Amphenol and others, or the AMP SEAL TITE connectors. These can be sourced from any good electronics vendor. I prefer MOUSER ELECTRONICS as a place to buy them due to the ease at dealing with orders in small quantities.
GENUINEDEALZ is a good source for marine-grade wire.
Electrical connectors come in a nearly infinite variety, and this can make specifying and ordering them a task that is far more complicated than the electrical circuitry they will connect. The line of connectors I mentioned as an alternative to the Deutsch products is called the TE CONNECTIVITY. See
http://www.mouser.com/search/refine.aspx?N=4292478053
for some guidance. You must order all the parts of the connector individually: the body, the contacts, the seals, and any sealing plugs. I don't know if you have the experience with ordering electrical connectors to navigate all the hazards. It can be a difficult process.