As already replied before, I think you're making a mistake. The 410's are gonna make 1st gear virtually useless. The higher rpm limit will help make the pace of shifts more to what people are normally used to in terms of shift cadence (I can't tell you how many vids I've watched of people short shifting a 350 just because they're used to the timing of gear runout in other v8's).
It helps that the 350 has a good overdrive and I'm assuming fuel economy isn't a concern.
But without a solid axle and fat tires to take advantage, I think all you're going to do is create a spin monster where 1st gear either must be skipped or half pedaled/clutch feathered and you'll have to do the same in 2nd to avoid rolling the tires over.
I guess what I'm saying is that unless you're going to improve the suspension/tire, swapping out gears is just going to make an awfully difficult car to drive.