These are the mounts I have no safety tab. Yes they are Anchor brand but made in China.
Those are nothing short of scary. What was the part no. (or... what year/model did you ask for)? You know, I only needed one mount, but after the experience at Autozone, I figured I oughta stock up. They had two of the US mounts, so I bought them both. Now that you say some of the Anchor mounts are being made in China, I'm thinking I should buy a couple more if I can find them.
I am not 100% sure about the NAPA ones yet but the counter guy said the 70's truck had the safety tab. We will see. I like the Old Round Guys idea of putting a bolt thru it. It is hard enough to get the bottom bolt started with out it being in a hole like safety tab mount.
Just in case he's wrong about the truck, you should ask for mounts for a '72 Corvette. The same mount fits both motors (350/454) and they're interchangeable right and left. You know, it really was a helluva coincidence that you started this discussion when you did. I could tell yesterday something was wrong, and today, the rubber pad in the left mount came completely apart. No telling how much damage it would have done if not for the safety tabs. FWIW, the mounts were installed by a previous owner, and the only thing I knew about them was that they had safety tabs. When I pulled the left side, it said "Made in Korea." The quality is so-so; safety tabs look good, but the body where the frame bolt goes through isn't very thick. The holes in both sides are wallowed out quite a bit as a result. In comparison, the Anchor mount 2285 has a double thickness in that area, very heavy duty. Unfortunately, that also means the original 7/16 x 14 bolt isn't long enough, so the car is down until I can get a longer one tomorrow.
Don't really have an opinion about the modification you mentioned, other than that there was no problem reaching the bolt between the safety tabs in my particular installation. Hopefully, the NAPA mounts you ordered will have the tabs and you'll be OK. If not, you might want to at least consider calling O'Reilly's to see if they have better mounts than the ones they sold you. If you can find the same ones they sold me, you'll be good to go. Man, it's always the little stuff that eats your lunch.
Jack