Here is a write-up I saved on this. I take no credit other than having cut and pasted it:
"After reading this post from Leonard from TX, I decided to go ahead and cut a hole in the driver side grill of the hood of my 95 R/T. Leonards suggestion seemed to make a lot of sense and since there was already a water drain hole in the grill, I figured that if Dodge wasn't worried about water entering the engine bay, I shouldn't worry either. After surveying the situtation, this is the procedure I used:
1. Remove the grill - 4 screws from the unerside. Cover the engine bay and the balance of the car with a drop cloth to keep off the work dust.
2. Cut away the hood insulation on the drivers side to match the insulation cutaway on the passenger side. You can make a template from the passenger side and use this if you are anal like me.
3. Use a compass or other round object 4" - 5" in diameter to draw a circle in the grill opening on the top side of the hood to match the location on the other side. I used a 5" circle figuring....bigger is better! Be careful to locate this circle so that it allows at least 3/8" clearance or more from the edge of the grill cover.
4. Drill four 1/16" pilot holes (12, 3, 6 & 9 o'clock) on the edge of the circle from the top side of the hood to use as referance points from the underside. Be careful not to let your drill bit skip over the paint!
5. From the underside, locate the four pilot holes. Take a piece of white chalk to draw the circle using a template to match the diameter of the circle drawn on the top side. You may need to use a free hand on the uneven portions of the underside when drawing the circle. Take your time on this step ensuring the circle is not outside the grill area! Check 4 or more times to be sure you have it right. A mistake here would be a hard pill to swallow!
6. Drill a hole just inside the chalk line circle using progressively larger drill bits until you can easly fit an electric sabre saw blade through the whole. Sharp drill bits are a must!
6. FROM THE UNDERSIDE OF THE HOOD, carefully cut just inside the circle with the sabre saw (medium tooth blade) from both directions until the hole is completed. Take your time, stopping occasionaly to check your work from the top side. You may need more than one blade to complete the job. Wear eye protection and a dust mask - VERY dusty and messy!!
7. Use a half round wood file from the top side to even out the circle so that it is perfectly round. Again, be sure not to go outside of the grill cover area.
8. Use quick setting two part expoxy to coat the cut edges from the top and bottom. Not sure if this is recquired, but felt it couldn't hurt to strenghthen the edge and to keep any moisture out of the freshly cut edge.
9. Cut a piece of 5/16" black rubber hose to length and carefully slit it down one side using a razor blade. (I found this part to be the trickiest part of the job!) Good thing rubber hose is cheap and readily available at the local hardware. Fit the rubber hose over the edge and cut it to length so that it fits snugly around the cutout. The hose seemed to easily go over the thinner and thicker portions of the cutout with no problem. The hose finished off the edge giving it a factory appearance.
10. Use black silicone rubber sealant by 3M to secure the rubber hose from the underside. In addition, seal the opening between the hood and the insulation with the black sealant so that the heat from the engine compartment will flow directly through the hole and not between the insulation and the hood. This step also finishes off the underside of the hood area nicely.
11. Clean the grill area and install the grill covering using the 4 screws. Take your time as these screws tend to fall into the openings, have a few extra "black screws" just in case.
The job took about 3-4 hours taking my time to measure once, twice, three and a fourth time time to ensure that I was drilling and cutting in the correct area. The finished project looks great (sorry no pictures available). The outside temperature was in the 30's and the heat from the engine bay was definately exiting this hole. It seemed that the temp guage was also registerring lower than normal.
I am hoping that this will help lower the heat in the footwell area. If not, the drivers side grill area definetly looks much better!! THANKS FOR THE TIP -Leonard from T "
