I have the FSD T-38 Talon and while looking for a paint I saw that there was a payware version and a freeware version. What is the difference between the payware and the freeware version?

I use the updated freeware version found on Sim Outhouse.

As far as I know the only difference is that the payware version has got a glass cockpit.
Here are a few screenshots:
http://www.fsd-international.com/projects/t38.htm

I do not know whether the real T-38 ever had a cockpit like that.
On all the cockpit photos I have seen it looked completely different.

I had the idea of upgrading the cockpit of the freeware T-38 to a glass cockpit myself using gauges of other aircraft.
Since I have the Flylogic F-5E I am already using the sounds, effects and several analog cockpit gauges for the T-38.

I have the Flylogic F-5E also. Would the engine sounds be the same for both the T-38 and the F-5E? The Flylogic F-5E has some very nice engine sounds.

PS: In case anyone is wondering here is a description of the T-38 update.
Description: A major restoration and tweaking of the freeware FSD T-38 Talon. MDL files tweaked for better canopy visibility and to fix the transparent fuselage when the lights were turned on. Improved VC gauge clarity and a much sharper VC texturing

The T-38 and the F-5 have the same design origin and use the same engines.

I always wanted to tweak the flight dynamics of that model. The elevator trim control was way out of whack.