Im glad you ask I think this will answer the question.
I've had this argument before. In support of the loadout on the 109f4
Some might say only structural improvements... hog wash!
For in game purposes
51B/C varients
NA-102, NA-103, NA-104-
P-51B-1NA
P-51B-7NA/P-51C-3NT
P-51B-10NA
p-51B-F-6C-NA or NT
"The -5 block added the alternate air source on each side of the cowling with filtered air and provisions for cold weather operations. A new Merlin -7 model was incorporated into the production line at the end of the P-51B-10NA block. Horsepower was boosted again, up another 50 to 1,450 at take-off. 91 model F-6C-NA or NT were created from -10 block of P-51Bs and the -10 block of P-51Cs. They had cameras mounted in the rear fuselage near the star and bars. "
51D/K varients
P-51D-5NA
P-51D-10NA
P-51D-15NA
P-51D-20NA
P-51D-25NA
P-51D-30NA
"The dorsal fin was added during the P-51D-10NA and later versions at the factory. Many other P-51s
received this mod in the field. Look on this page, there is a wartime pic of a -5 model with the dorsal fin. Metal elevators were added in February 1945. The P-51D continued to have a fabric rudder. The -25 blocks and later were fitted with attachment points for various forms of
rockets and rocket launchers.
One of the most important improvements to the P-51
was not structural. The K-14 gun sight was introduced in October of 1944 to the -20NA and later blocks. This new gun sight helped the pilots score more hits especially in higher deflection angle attacks. The K-14 utilized an analog computer. The pilot had to dial in the wingspan of the enemy aircraft and the range. Then all he had to do (sounds easy) was to put the enemy aircraft in the gun sight and pull the trigger. "
http://www.mustangsmustangs.com/p-51/p51variants/P-51D.shtmlWe have 1 51D that does it all... where the 47 variety is at least done right. If the 51's can have improvements made from the field {Field mods} why cant the 109F-4 one of the most important 109's Fritz/Franz or Frederic?
Perk it! Fine by me! but it should be availible. hell the 109e carry's a bomb/dt.
Gimme Back my Bullets,