When completing repairs to my bus, I want to switch out the heavily rusted nuts and bolts as needed.  I am having trouble finding the identical nuts/bolts in metric sizes that match my owner's manual (the existing nut/bolt) and the general internet instructions for repairs.  Not only is this compromising the integrity of this great vehicle, but also I think long-term this could be an issue by swapping out metric for SAE sizes and possibly stripping out nuts/bolts during future repairs by not realizing its a SAE nut/bolt or creating a problem for the next owner (my son hopefully).
 
Any suggestions?
 
 
jabin
1987 Vanagon Transporter