Variable hydraulic lifters for 440 engine

Ok, so i checked what engine and transmission do as you mentioned.

I had screwed around a bit before with the choke and had played with the idle adjustment, so at the first test it run around 900rpm idle and at that time the wheels did start to spin in Neutral.
The speedo cable is broken but my guess would be the rotate for maybe 10mph, if i put my foot against it i could bring them to a stop though.
When looking at the rpms and vacuum there was a loss, it seemed like being in drive already.

But then i realized the rpm was 150 too high so i brought it down to 750rpm idle.

When at idle in Park, i have around 750rpm and 6" vacuum.
Putting it in Neutral, the rpm's drop slightly to 730-ish and vacuum drops of a little, maybe 5.5"
The wheels don't spin continually, but they rotate a little bit at the time but just small amounts and if i grab the wheel i can just hold it stationairy.

So as a result of this, i believe letting the engine run in idle above 800rpm just worsens the situation as the converter will start to put a load on the engine.
So sticking with 700-750 rpm would be the best option.
But it could mean this torque converter is too tight for this cam, but a flash stall of around 3000 rpm is ok.