my s2 erst has been sat in the garage for over a year now since its engine let go , and i got almightily pisssed off with it!

but now i want to get the car minted up and running a treat for the summer. However...i want to check the car for rot before i throw more money at it, the body work is very good with only 1 or 2 rust spots. But i have no reason to think its rotten as the cills etc are in good condition but i just wana be sure...
Any info on how to check for rot would be much appreiated! Thanks!