It's always a dilemma when talking about pinion angle and considering future mods such as a lift or SYE.
I assume you have stock suspension right now. You could either set the truss to the same angle as stock, throw the 8.8 under and probably be good. OR set it a couple degrees higher in prep for a lift and possible SYE. You have to be mindful because anytime you go adjusting the pinion angle with control arms, the truss is no longer at 0 degrees, which is where you want it for track bar angle and clearance.
It's up to you and how much money you want to spend because if you set the pinion angle up a couple degrees from stock you'll probably get vibes and need adjustable control arms now to adjust it back down until you get a lift. Then once you get the lift, adjust the pinion back up and everything is good.
Or set the pinion at stock and run it. But then when you lift it you might need adjustable control arms to raise the pinion if you get vibes or do an SYE, but now the truss is no longer at 0 degrees.
In the end, if you're only considering a couple inches of lift, differences in pinion angle are fairly minimal. I set my pinion angle with the truss at 12 degrees (IIRC). I only have 2" of lift, and am currently using stock arms and no SYE. Cruising I don't get vibes, but on acceleration the pinion lifts up enough to give me vibes.
The next step for me is JB Conversions super short SYE and some savvy adjustable arms. With the super short SYE my guess is the amount I will have to raise the pinion is very small.