The pushrods in my 340 are hitting the roller rockers. The ones in it now are 7.5" long.
Sounds like you need some shorter pushrods so you can run the adjusters down a little to keep the pushrod cups away from the rocker arm.
Those are the ones I got. Sounded short when I looked a the mic but they work.... the need to be the 7.38 inch rods so you have more adjustment screw sticking out/down out of your rocker....
You need the tool in the link below to properly determine what length pushrod you need. I had to have smith brothers make me a set of pushrods shorter than any set I could find. I think they were 7.200.
http://m.summitracing.com/parts/cca-7709-1