My 408 liked a lot of initial advance and started great cold but then could barely spin if you needed to re start a hot motor.

I ended up putting a seperate switch (kill switch) on the ignition. What I would do is engage the starter and once it started spinning I’d turn on the spark. Worked great.

I also went through the remote battery needs a ground thing I hooked an old thick beat up arc welder cable from the batt ground in the trunk all the way up to the stud where the starter bolts to the bell.