So you got me interested and I went to the bin to check it out.
Both of these come on flat cardboard sheets, with film on the fronts. The film keeps the letters in the proper spacing until they are set down. You pull the backing, lay it down on the car, and when you have it correct, you press the set down, and remove the film and voila!
The letters for both cars are the same height and type face, and very similiar color, despite different color codes.
LR3 "ROVER" measures 15 3/4 from edge to edge on the bottom of the "R", and you can see a definite "bow" to how they are set, so that when they are placed, they follow the back curvature on the metal. A straight edge underneath reveals no significant curvature to the letters, they are essentially flat, and if you look at your hood, that is an essentially flat surface.
SII "ROVER" measures 14 1/4 from edge to edge on the bottom of the "R". The word lay is essentially straight. A straight edge underneath reveals a significant curvature to the letters. The hoodline of a Discovery has a pretty good curve for the letters to sit on, and they are formed as such.
Bottom line, different. You could probably make them work, but it would be a ton of work to get a quality outcome.
As for improved part #, I show:
"LAND"
DAB500050LQV up to 6A376899
DAB500050LQV after 6A376899
"ROVER"
DAB500080LQV up to 6A376899
DAB500080LQV after 6A376899
I did a search, and if there is a new and improved #, I do not know of it, and with everything else going on in Land Rover, I could have missed it. Thanks for the challenge. Going back to work now.