Would you really be able to put 4.10s in? Cause these are the available gear ratios for the T56 and then for the 3650.
T-56 3650
Gear A B C
1 2.66 2.97 3.36 3.37
2 1.78 2.07 2.07 1.99
3 1.30 1.43 1.35 1.33
4 1.00 1.00 1.00 1.00
5 0.74 0.80 0.80 .67
6 0.50 0.62 0.62
So if you use the C gearset, you're only looking at about a 200 rpm drop at 100mph with the .62 ratio as opposed to the .67 in the 3650.
The only way you could really do the 4.10s is if you got the A gearset, but then you're dealing with a 2.66 1st gear, which is just about equal to the 3650 1st gear with the 3.27s. So really you're trading off 1st gear in order to get a low 6th gear. So I'm not sure the 4.10s are really viable.
I was thinking more along the lines of getting the C gearset, that way things would be about the same as they are now, with a 6th gear a little higher than the 3650 5th, and a 5th gear a little lower than the 3650 5th. That way 5th is more usable right off the bat, and you can later swap in 3.73s. I just think there's too big a trade off for the 4.10s. This is just me talkin though. It's all theoretical for now.