Putting new (different color) seat belts in My 84' Carrera
 

I am thinking of replacing my seat belts in my 84' Carrera. I want to put red color belts in. Has anyone done this ? Was it a kit ? do you just replace the belts ? what ? How much approx ? Any suggestions for sources ? Can I do this myself or am I opening a huge can of worms ?

I have RS style doors on now, They have red pull straps. I think red belts would look cool.

Thanks in advance