How to win friends and influence people on forums! Ask them for advice - then call them out for offering up bullshit. Nice one....

The 'stock truvativ' cranks you refer to - are they on a 57.5mm chainline? If so, you are right, it ought to be simple.
If they are 50mm cranks (to suit the BB shell), it remains a right faff (as I've explained), but it's do-able and gives perfect chainline and all gears are usable.
Fact remains that with a 68mm shell and 150mm back end you are seriously limited on what cranks you can use.