"Silent" timing chains which were standard after all the NVH improvements established for the 1996 model year are notorious for stretching. Your cam timing is a few degrees retarded from even 10K miles of wear.
Earlier HO engines (and maybe Renix too, not sure) came with a single row roller timing chain. Hesco sells a replacement, and Cloyes has a double roller chain, though it's pricey.
When you see how much slop is in a 100K mile+ "silent chain" you'll be happy you replaced it.
You'll need a harmonic balancer puller to remove the belt pulley/balancer, and your one-piece oil pan gasket should be okay after removing/replacing the timing cover . Aside from the tight space in front of the radiator (might just pull it out for the task) it's quite straightforward. You may need a gear puller to get the old crank gear off, some will be more willing to budge. Replace the harmonic balancer seal on the timing cover when it's off the engine. Be sure to put the oil slinger back on the crank before re-installing the cover.
A worthwhile endeavor, and you'll probably notice the slight boost in low-end torque from bringing the cam back in-time.