I use the Phillips PCS 130 as diagram shows at top of page 2.
In camera correct looks less stretched so is better if you can do it.
There are two problems with any of these systems, focus and uneven exposure.
I first set up the print with a paper that has straight lines on it so I can see if lines are parallel. Then I focus on the sprocket holes by tipping the lens and then using the enlarger focus bellows. That way you get focus across the whole neg without stopping down. Exposure is solved by using a dodge card. Start the time covering the whole print and uncover the wide end first moving uo toward the narrow end.