Wood Worker's / Wood Flooring Help!!!!!!!!

[USMC-8154TL/DM]

I am planning on redoing a room's floor in the house with wood flooring. I aquired some 40+ year old pine T&G - 2 3/4" wide x 11/16" thich (I think); the flooring was originally used a wains coating. The back side is flat and the front side has a V groove down the middle. I am going to plane both side down just enough to get a smooth finish and finish it off with a finish sander, stain to desired color and protect once in place. Both the T&G sides are in great shape and fit well together.

I guess my question is could I use pieces that are 8-10 inch in length with one that are 24-36 inches in length? I was planning to do a 220 sq ft room but alot of the wood had to be trimmed from rot or termites. I now have around 75-100 sq ft. I will be doing another room instead of the 1st choice.

Anyone have experience in this area. I have a good bit of wod working knowledge but nothing in flooring other than ceramic tile. I know I could go to Home Depot and buy good flooring and lay down, but I like the idea of doing it myself and it would be a waste of good wood by not using the 40+ pine.