Any recommended process to change color in accurate way

I would use a color layer with the precise wanted color

Then I would setup the blending mode to color

Then I would do a little masking

I seems to work not that bad…

I'm in agreement with D Fosse because you have lights and darks, not a solid color area.

I would do something like this and then tweak the results afterwards as needed:

Create a new layer on top.

Start the way you were already heading -- Edit > FIll > Color. When the color picker opens, either click the color swatch attached to the tank top on the model or type in the color code. OK. The layer will fill with the chosen color.

Select the tank top and create a layer mask on the color layer.

Change the layer mode to Color.

Tweak from there as needed.

A color number doesn't really apply because highlights and shadows change it. You need to decide which exact spot is neutral light, and match it to that.

Quite frankly, I'd just do this by eye. It's not all that difficult. To pick just one adjustment tool, Selective Color can do this quite easily.

A numerical match is only possible with two flat areas of perfectly flat color.