2016, 2nd year @ Silhouettes

[alfajim]

I'm a newbie here all around, to the board and BPCR I am going to use an original trapdoor for shooting I am not going to jump in and get any thing more just have fun with this one at the range and some matches it fits into.
Being new I have no idea of the rules or requirements for silhouette matches or if I am able to shoot in them. I am 73 now and have had both knees replaced so if prone getting up and down is difficult and kneeling is a total no no.
I have seen mention of people shooting sitting can do that, and standing "off hand" is good for me have been shooting that way forever Army and a number of years trap shooting. Carried a 22 average in trap and expert with the 06 Garand they made me an assistant instructor at the rifle range trying to teach the un knowing how. I am also a left hand shooter so that made it harder.
So if I am going to do silhouette I need info on the procedure to do so and if it is even possible with a trapdoor. What do ya all think?

Jim