:welcom: J.wms to iboats. Nice to have a new member...
I am not sure for '73, but I have a '76 and I am using this setup;

It is a typical two handle setup that works the both the throttle and gears. I refurbished it from what it once was.

And was even able to find replace parts for it yet as well. If you don't presently have anything, you could even adapt the same or other remote control units to your engine.
Let us know if you have anything presently and even mote info about your boat and engine. JMHO