Transmission Shifts 1st to 3rd, No 2nd Gear!

[62roadster]

My '61 Cruise-o-matic starts out fine, starts out in 1st but shifts immediately to 3rd, no 2nd gear, no matter if I step on the petal as a normal take off or if I put it down relatively hard. Also, when cruising in 3rd gear anywhere 45-50 mph and push the petal to the floor, the engine only "revs", doesn't engage any gear until I let off it and then it's back in 3rd again.

I have replaced the vacuum modulator and the downshift/kickdown linkage is adjusted properly; what can be the problem?,,,