I had the same problem. I had to shim the engine up quite a bit for more clearance. Then I bought a different oil pan #971 and cut a notch out and welded it back up. It still rubbed a little. I didn't notch it enough. So I took a piece of angle iron and glued it in place with some silicone. Now it rubs on the angle iron instead of the oil pan. It will take years to rub through 1/8'' angle iron. I just check it once in a while.
when turning left everything clears, but turning right the idler arm center link hits the oil pan..it has the v8 center link, and the 187 pan....
When I installed the 383 in my '68 Dart, I had the same problem when using a 187 pan! I know it is written out there that this pan is the solution to that problem (for a '67-up A-body), but it is simply "close" at best. The "heel" of the center link just inside the idler arm makes contact with the corner of the pan right where the clearance cut-out ends! And if we're talking about your '65 Dart, your car is even narrower between the frame rails, which I imagine exacerbates the problem!
I bashed mine with a hammer to extend the length of that cutout a little more toward the rear. Still not perfect, but better.
They now make a reproduction big block A body oil pan that has the correct divot for that clearance, but you may need an even bigger cutout. The following is the pan (# 893) that was reproduced for the '67-up big block A cars:
*** Can't post a link yet, but you can find that 893 pan on Ebay *****
Or did you solve this problem already? If so, let us know how. I'm actually curious about how that works out in an early-A car.
I too had major idler arm side pan interference on my 69 cuda. Parts used are; new aftermarket lower ball joints, new aftermarket idler arm, and new NOS OEM pitman arm. After some struggle and head scratching I got called away from the job. When I returned a few minutes later I approached the car from the rear and could see the center link and tie rod end geometry didn't look right at all. The right side tie rod was at an obviously steeper angle than the left side tie rod. So I measured from the lower ball joints to the floor to find out if the car was sitting level on the lift, it was +- 1/8". Then I measured from the outer tie rod ends to the floor, they were the same +-1/8". Then I measured from the inner tie rod ends to the floor and found the right inner end to be 3/4" higher than the left inner. Only 2 things could cause that, either the K-member was grossly bent at the idler arm attachment, or the aftermarket idler arm was shaped wrong. Comparing the K-member with another unit confirmed it to be OK. The problem was the shape of the idler arm. So I froze both ends of the idler arm with a can of freeze spray, then fired up the torch and did a really fast heat at the idler arm bend closest to the K-member then pulled the center link end down until it matched the pitman arm height. Now the angles of the left and right tie rod end links are identical, the center link is now level, bump steer has been equalized, and now I have plenty of oil pan clearance without having to hammer it. I don't remember the brand name of the idler arm as it was bought years ago in preparation for this build.