203 shifting prob

[biggreenchevy]

Ive got th350 with a 203 t case on the back and its Pita to get it to shift from 2hi to 4hi most of the time
Ive got the part time convert in it now.
Ive put a longer shifter on it but it is still hard to shift.
I know 203 are notorius for this but what have you guys done to fix this
Ive switched back and forth on two stock shifters and its still the same

So do you guys think its in the shifter or the t case
and wat can I do to fix short of just getting a doubler from ord like i want to do(ive got a 205 to do it)!