Picatinny and weaver rails

Hi,
Quick question.
Can a picatinny or weaver rail be fitted to the SX3 as there are 4 indents in the top of the gun that must serve a reason?
Also thinking of attaching a light underneath for lamping and wondered if anyone has successfully fitted a rail under the front grip?
Quick question.
Can a picatinny or weaver rail be fitted to the SX3 as there are 4 indents in the top of the gun that must serve a reason?
Also thinking of attaching a light underneath for lamping and wondered if anyone has successfully fitted a rail under the front grip?