i had AN6 from swirlpot to pump. it ran lean as pump was trying too hard to soooook.
swirlpot to 044 should be 15mm (id 13mm)
Compared to what? I ran 400hp on a all -6 set up for about a year until i went for more power, i found the main issue with my set up was the tank pump, it ran dry every time i went round a sweeper on track days even though the Swirl pot kept fuel flowing to the main pump, which in turn meant the Intank pump died. The other thing with feed lines is keep them as short as possible, mine was 3" long.
There is of course the position problem, if you mount the pump higher than the tank/Swirl pot you will have feed problems (044 like to be Gravity fed) they like to be lower than the fuel tanks.
IMHO i\'d rather run an 044 with -6 lines than an 044 Intank (every thing gets map tweaks for anything that could alter fuel delivery or AFR anyway so thats no issue), the first track day you do (intank) will show you how bad the stock tank baffles are, i didn\'t need to look at the fuel gauge i could tell when i hit 1/2 a tank by the big Splutters on corners.