1970 Dart Hood scoop and pin hole sizes

[sublime 340]

I have bought a used hood for my 340 swinger and now have to install the hood scoops and hood pin holes. I want to drill all of the holes before it gets blasted and painted. Could someone tell me what the proper hole sizes are for the scoop holes and the hood pin holes? Someone told me one of the scoop holes is oval, is that correct?
Also, for drilling the pin holes is it best to try and fit the hood first and then mark it or drill through the centre of the locations on the hood underside?

 

[1994redram]

I pressed cardboard over the studs on my scoops and traced them out. So I had a perfect template of the scoop shape and stud locations. I centered two holes from the bottom of the hood and drilled them out. Then set the template on there and used the two drilled holes to align it. I used a drill bit one size bigger than the studs and the scoops fit great. I'm sure the factory holes are bigger to allow for manufacturing tolerances.

I think I used a 4 inch hole saw with LOTS of lube to cut the big holes in the hood. It worked great but It trashed the saw after. A quick touch up with a roloc disc cleaned up the burrs. The scoops were the first thing I did after buying and getting the car running. Still had 20+ year old tires on it but it sure looked sweet while sitting on the side of the road with a flat!

 

[70Sbird]

I just happen to be doing some of this same research myself. Here is the drivers side hood layout from the top, the hole sizes, and a pic of the bottom of the hood:
The elongated hole is at the front outside hole of each scoop. I didn't pay any attention to the hood pin holes as I wasn't going to be using those - sorry

 

[Mopar to ya]

Can't help you on the twin scoops, I have a dual snorkel. I had just had the hood painted after the hood scoop and decided to put in hood pins. There is a small indented place where the pins are intended to be mounted. That didn't work well with my hood curve.I installed the pins first in the location I chose, then put a dab of my daughter's nail polish on the tip and closed the hood. I marked the spot with a spring loaded awl. I couldn't make myself drill until I checked it six or eight more times. I used a step drill and it fits so well I can slam the hood and the pins don't hit or bind.

 

[DartGTDan]

I purchased the hood scoop grommets/seals from Detroit Muscle Technologies. I then used a 4" hole saw, but should have gone smaller. I suggest trying different sized hole saws to find the one that fits your grommets/seals the best.

 

[DartGTDan]

Double post, sorry!