I think the flame trap on your '81 is about where it was on the '84 I had. That is, it is on the intake side, under the manifold. It is really not as bad a job to clean as you might think; it's just that the whole job must be done by feel. There is not way you can see what you are doing. It is hard to tell someone else how to preform the operation, because, as I said, it is a "feel for it" thing. You need to find someone to show you, then you can do it from then on. Ipd has a relocation kit that you can use to move the trap housing up above the manifold, so you can see what you are doing. That is something you might want to consider, once you find out where it is on you car.
Occassionally cleaning the flame trap and associated hoses really is something you need to be doing!