[Cammer-6]

The other big question I have is your transmission cable.
Theres a ratio of cable pull to throttle opening position
that must be adhered to regardless of cable slack etc

Im pretty sure I was the beta tester for a 200-4R behind an OHC-6.
I think it was late 80s I did swap to a Monte Carlo SS(same trans as the Grand National)
I had an engine on a stand with carb set up and put the trans minus pan next to the engine.
When the pan is off you can see how much slack is in cable until it bottoms out.
I made my own bellcrank and slotted it for adjustment.
As it turns out my benchtop adjustment was spot on and havent touched it since.
Glenn(aka Birdman or Einstein) and I drove to a buddys shop with trans in the trunk.
About 4 hours later we were test driving with the ST300 in trunk.
Again the ratio of throttle opening to cable pull is paramount.
Many a trans has been fried in short order if its not correct.
Im not near my notes for that,perhaps I posted it around that time,
but PY has crashed a few times since then so may be lost.