The best thing is to leave it in it's original condition. These rifles are going to increase in value drastically when the current flood dries up. Those in original condition will be worth far more than those that have been altered. Collectors will not buy a rifle that has the finish tampered with or the stock sanded or refinished.
An example: One year ago I was buying Chinese T-53s for $79.00 each, now you are hard pressed to buy one for $150.00. Try making that return on stocks. In the five years I have been collecting these rifles, the value of my collection, overall, has more than doubled. For those who have been collecting longer than me, some of their collections have increased 500% or more in value.
"It is better to be too skeptical then too credulous"