Questions about AC Delco Distributor caps and rotors

[1967RS/SS]

I will be buying some tune-up parts for my 67 350 (original engine) and was wondering the difference between AC Delco parts.  They have listed on Rock Auto and the AC Delco website parts catalog two different p/n's for both a cap and rotor. 

Caps listed: D308R vs C349

and

Rotors listed: C435 vs D426R

Anyone know what the differences are?  I want to make sure I get the correct parts the first time.  Thanks...

[JohnZ]

I will be buying some tune-up parts for my 67 350 (original engine) and was wondering the difference between AC Delco parts.  They have listed on Rock Auto and the AC Delco website parts catalog two different p/n's for both a cap and rotor. 

Caps listed: D308R vs C349

and

Rotors listed: C435 vs D426R

Anyone know what the differences are?  I want to make sure I get the correct parts the first time.  Thanks...

There are at least 30 companies making replacement GM ignition parts, and Delco hasn't made any for over 20 years; AC-Delco doesn't make them either - they're just a marketing division, and buy the parts from outside suppliers (without any GM identification) and put them in AC-Delco boxes. If you want "the real thing" with the "Delco-Remy" logo molded into the parts, you can find them on eBay, although there's a GM-licensed reproduction Delco distributor cap and rotor on the market now that's pretty accurate.