Correct paint finish for inside bumpers 1969

[CobraR1339]

Trying to re-do inside of bumpers in the correct finish since it's ground up , I suppose I might as well do it factory ?

The car is Irish Green, the inside of the front bumper is just primer grey with some green drift at the edges, primer runs, etc. Believed to be 100% original, never been changed as far as I know. Does this sound right?

The rear bumpers are the same way, but the drift of green is far more pronounced in spots.

Recommendations for the correct finish please...paint is pretty much done except for the inside of the bumpers. Obviously the primer and a drift is easy to re-create.
Does this matter on a 69 911 ? Tempted to just make them glossy and pretty.

On another note, since this car had original paint as far as I can tell. Just for reference . . The under body appears to be grey, with green overspray drift from when they shot the rockers , front and rear. The it looks like they blacked out the pinch weld area, wheel wells. After all the pics I have seen, I thought 69 underbodies were black and 68 grey ?. Looks like they did not change up from what they did in 68 yet for this car.