Messed up firing order? I need help!

[pehlen]

So like an idiot, I replaced the distributor cap, plugs and plug wires on my 66 convertible without documenting them first. I have the shop manual--I assumed it could be nothing else. Now I can't get it started.

I've tried 15426378 and 13726548 but neither works (although the latter sounds better). The engine was replaced in 88, but it looks stock, at least it seems to be stock, it's painted blue, etc. The origininal intake manifold is on it and it has the firing order printed on it but I'm thinking that a different cam must have been used in the rebuilt engine. I've verified that there's spark at the coil and to the plug wires and there's gas in the carb.

I initially replaced all this crap because I was getting backfires and stalls at idle which had never happened before. I had replaced the fuel pump a few months ago and haven't put many miles on it since then, but it ran great after I did that so I don't think that's related but who knows? If it's caused by the fuel pump is there any way I can test that without just going ahead and replacing the fuel pump again?

Can anyone help with a suggestion of another logical choice for a firing order or another idea why I can't get it going?

TIA