Restore or upgrade?

I received this car from a widow whose husband bought it in 1968. Have the sales receipt, original title and warranty book with protecto-plate. Need some TLC. Should I go back to original? I’m not crazy about the power glide transmission but it’s a one owner matching numbers car.

I did spend two hours this weekend and got it running. Actually runs pretty good. One lifter tick and a front transmission seal leak I haven’t tacked yet. Let it sit over night and fired right up the next day.