No need to roll if you trim though. The outer wheel house is you first interference if you trim the lip to 1/2" or so. As for mounting your wheel well moulding, same problem weather you tim or roll, you still going to be relocating the top WW molding screw.
On 69s especially, because of the squareness of the wheel openiing, I have had outer panel damage trying to roll the lip. A 67 / 68 is much rounder and much more freindly to roll. If you try to roll instead of trim, you will need to relieve it at 10 and 2, then your going to have a ****ty looking tranasition, but I guess no one would see it.
If it were me I would trim, if you cut out the spot weld you could do a couple quick stitch weld on the inner / outer edge with a water rag on the outer panel. Maybe less chance of damage then rolling
I just went in the garage and poped you a quick pic showing exactly what I was telling you. 10 - 2 trim to 1/2". This is with a 345 / 30 / 19, it dont come no bigger or ride height no lower. Tire look fine to me.