Magnum Exh Manifold options

I’m looking for a little information from the experts in here. Way back in the early 90’s I put a set of Magnum exhaust manifolds on a 340 truck project I had. Just basic 1.88 heads and I don’t recall the exhaust ports being hogged out much if any. The gaskets and manifold ports weren’t a perfect fit to the LA ports but I ran them anyway. Fast forward a couple thousand miles and it burned a small section of the gasket out, and it was a repeat performance every couple thousand miles. I want to say it was the outside ports but don’t recall.

I am building a 72 Scamp project and at the point where I need to select an engine for it. I am considering a magnum engine but I know the Magnum manifolds won’t fit in that body.

I have looked around and some people say the LA headers and Exhaust manifolds work on Magnum heads and some say they don’t. I don’t see any headers available for the “A” bodies that specifically say for "Magnum engines only".

For magnum swapped engines, what are people using for manifolds/headers? If using the LA headers, are you having issues with burning out gaskets?