Depends on how much you went to spend I guess, and whether or not you're looking for a bling factor.
Personally, I think any good silicone wire at least 7mm or larger in diameter is good. I prefer black, for that stock appearance. AutoZone used to sell an inexpensive (~$40ish) set of black wires, 7mm I think, that I've used on a couple of V8 engines in the past. I have MSD wires on my Corvette and I like them very much.
There are a few tight squeezes around the steering column, so boot style can be important on a Pontiac. I haven't bought plug wires for a Pontiac 400 in about 20 years, hopefully someone with some recent experience can chime in on the clearance issues.
'68 GTO, 400/TH400, AC/PS/PB/PW/tilt, hideaways, Hurst dual gate
'72 442 'Vert, 350/TH350, AC/PS/PB/PW/tilt
'71 Javelin, 401/4-speed restomod
'74 Corvette, 383/4-speed, 450 hp, restomod *SOLD*
'70 Cougar XR7 'Vert, 351W/FMX auto *SOLD*