question on vin number and tire size

[pointer80]

Hello all, I have two questions. My first question is about the vin on my 1993 chevy extended cab 2wd long bed. When I run the vin online it keeps coming back as a 6.5 ft. bed. Just wondering why? The other question is my truck currently has 15 inch rims and was wondering is that what it come with stock on 93 2wd? I would like to get the biggest(tallest) all season tires possible just too set the truck up a little taller for more ground clearance and looks. Also can I go with 16 inch rims? The rims on there now are a nice set of chrome American racing rims and I would like to keep them if I can still get the taller stance I am looking for. Thanks in advance for the help.