Having an issue fitting an intake on a 440. I have tried three different intakes but all seem to sit too high even without the intake bathtub gasket. I am starting to think that the block has been decked. Is there an easy way to tell if I am correct or do I need to pull the heads?

Either the block has been decked or the heads have been shaved. You may need to have the intake milled to fit. There may be a known outside measurement of each to compare, but I don't know what it is.

what Bob said. Might have to cut it .030 I bought a new RPM years ago and had issues like that. I had it cut .030 and was able to use the paper and pan gaskets. If it fit's on top w/o any gaskets than yu can get away w/ the pan, but it sounds like it's still off. No big deal. You might be able to find one on e-bay already cut if you look hard.

all the newer edelbrock intakes are too wide.

Some shops will deck the block but not cut the valley end rails so one way to tell if the block has been cut a lot is to set the intake gasket in place and check the port and bolt hole alignment , it will be too high just like the intake .

What intakes are you trying to use ?

The Performer RPM I put on the 505" 440 stroker fit, and the block was even decked a bit.
I do have the M1 intake from my old 451" 400 block that was milled 0.100" on each side for it to fit.