Toyota makes two styles of forward type shift rods;
4.5" 84-88 carboratored G52, G54, and 86-87 EFI turbo R151F
4" 89-95 EFI p/up, 90-95 4Runner.
Yes, the t-case would have to be opened up and the rods replaced.
We have many rods in stock-sounds like a trade up 
Give us a call 8) 8)
Marlin
When my G52 craps out (if ever, over 220,000 miles and still going strong) I will be calling you, either for a W56 or R151F upgrade. Running 4.88's now, so a lower 1st would be really nice.
