I have to disagree with MOPE a good bit working backwards on his list and say that the 340 has the HP advantage without a doubt. Not the torque. (IMO at least.)
2nd, pulling the 727 for a 904 is a pricey thing that includes driveshaft work.
IMHO, the following parts would be a better bet.
Open air cleaner
750 Holley/800AVS Thunder
RPM intake
RPM heads with some minor work done
(This over stock heads with a bowl porting and 2.02's.)
1-3/4 header - 2-1/2 exhaust
3.91 gears
My only two concerns are where the pistons sit in the hole and the cam to be used. These two areas as I read the read are a bit grey to me due to your goals. One feeds the other and to properly answer the question i need more clearity.
Just as an example, Edelbrock claims 417 hp with there set up which includes there cam, which I am not exactly a fan of. Add some duration for a street stripper. 10*'s ought to do it. (Hyd. cam)
To copy cat a build is not a shameful thing, but give accolades to the original builder.
Just food for thought.
This doesnt see, to pricey. Would i notice a big i improvement over my stock one?