Engine swap 318 to 360

just something that has more sound and guts.
Well. With a low-compression 360LA this is a tall order.
There is only one way to get the sound, which is with a bigger cam.
And, the bigger cam will make it's power several hundred rpm higher up in the rpm range, while trading away power at the lower rpm.
There are about three ways to overcome the low-rpm power-loss;
1) eliminate the lower rpm with a hi-stall convertor, or
2) increase the cylinder pressure, or
3) increase the remaining engine torque with TM (Torque-Multiplication), thru the gearing, or
4 ) some combination of all three.

In your case, having a 318, you already know what she feels like. so then, you can lose quite a bit of lo-rpm performance, before it starts to feel like a 318 again ..... but it will, with the wrong combination of parts.

If money is an issue for you, you will quite probably end up, disappointed.
If you can live without the big-cam sound, you will be much money ahead; just slap a "hi-stall Convertor" on her, and some performance rear gears, plus a 4bbl/dual-exhaust; and call it done.

I'm not looking to be a street rod just something that has more sound and guts. Yes I know for sure it is the 904, if I don't want to hot rod can I just get the plate? Also what are the down sides to just getting the plate and nothing else?
Yes, you can get just the proper flex-plate. But I would at least install a shift kit, to deal with what you are already contemplating, as to "sound and guts".