It makes me nervous to see plunge cuts with circular saws being suggested to those not-so-experienced with tools and tool safety.
Just as good a result, in not much more time, can be achieved by drilling good-sized holes in each of the 4 corners, then 'connecting the dots' with a power jigsaw (or sawzall=reciprocating saw, if you don't mind a somewhat hairier result). You can borrow or rent a power jigsaw if you haven't got one.
Good luck, have fun, try to keep all fingers/hands/feet/eyes attached and in original condition,
Pat
Just as good a result, in not much more time, can be achieved by drilling good-sized holes in each of the 4 corners, then 'connecting the dots' with a power jigsaw (or sawzall=reciprocating saw, if you don't mind a somewhat hairier result). You can borrow or rent a power jigsaw if you haven't got one.
Good luck, have fun, try to keep all fingers/hands/feet/eyes attached and in original condition,
Pat