Correct the red interiors in 68 and prior definitely have a pearl look to them ( my 66 is said interior ) Where as 69 red interiors are very much a tomato red that has zero pearl tint to it
And Yes, red stripe was avail on pretty much any exterior color, just some may not be ' non recommended' so to speak .
As far as a 15" steel wheel with beenie hubcaps was standard on Hemi cars in 1968 but not 100% sure of they were avail non hemi cars unless it was a police car or taxi . SO maybe keep that in mind on power train choice
1968 hemi cars would have F70-15 tires ( same goes for 1969 btw )
the 1969 A12 was G70-15