Looking very good H. Give the primed areas over the joints a light rub-down, with fine wet n' dry, to prevent a ridge under the paint when applied. Should look good with the paint on, well done so far.
Try Humbrol 153 Insignia Red if you can get some, or add a touch of Black to 60 Scarlet Red.
Whatever you mix, it should be a bright red base colour with a slightly darker tonal value.