i have a set of new GM Doors for a newer K-5. I just got a free K-5 that i was told was late 70's so i thought that i could use the doors. when i took a look at it i saw it is a 73-75. Will the new doors work if i chop them? The whole truck is mostly rust but i have new GM fenders and just picked up some free GM bedsides inner and outer so i have almost a whole new body for the thing.