Pickup transmission interchange

[noisytoy]

Have a 79 2WD long bed pickup. The 5spd trans is shot- stuck in 4th.
It used to jump out of 4th and 3rd gear synchro is bad too.
I want to find a used trans and put it in. What years interchange.
Is it just 79 and 80?
I've seen alot of pre 79 transmissions in the wrecking yards.
I think the driveshaft is different, right? Anything else different?
So I'm wondering what year transmissions fit in with no or only slight modifications. Don't want to do alot of fabricating.

[noisytoy]

With all due respect, not getting any answers here. Anyone know of transmissions gurus that would have information?

[JeremyH]

Why not just replace the synchros??

Probably cheaper than buying a tranny from a boneyard.

However, if you still wanted to replace it, I think the only things you need to worry about are the input/output shaft spline count and wheter or not it fits (dimension wise) under your truck. You can always get a tranny mount for that transmission and make it work on your truck.