Timing.... It either bogs or wont start

[85pig]

Can you pull the radiator and do it in situ?

I'm no kind of expert with the 4.9-6 so I will leave that to others.

But I definitely wouldn't butcher my throttle plate, because while it isn't a "big" cam the valve event timing is all wrong for what you want.

That's doable with the 300. Obviously kind of a pain (and guiding that 10 foot long cam back into the block would be fun), but it's an option. If a guy was to do that, he could also see if the previous owner used an offset cam key to bump the timing up as well.