46 degrees of overlap and it has a stinky idle?

That's not a very large cam or have much overlap.

Here's what I might do. Double your initial and reset the carb using a vacuum gauge to highest reading, leanest mix setting. Then maybe out 1/8 turn. As long as it starts when warm without dragging the starter, that's a good starting point.

I don't even run stock 318's at 8 BTDC, nothing I have has less than 14 initial. Throw the book in the trash because the timing events from an FSM were not to optimize performance. They had emission profiles to meet, even back then. I'd figure out the total and tailor it after setting initial before you hurt the engine.

If you don't have a timing tape or marked balancer, find a post with "hillbilly timing tape" and do that so you can determine total. Just don't drive around with an excessive amount of total, bad things happen...
It takes some work to get ignition timing right, but, the benefits of a clean running engine are worth the time.