A single bar plate is a single bar plate and they just flow what they flow. Nobody makes a "magic" plate. The obvious answer is a larger bar with more and bigger holes......BUT it doesn't work that way. Companies make plates with 1/4" bars but they flow no more. Has to do with back pressure on the bar. More engineering in a plate than people think.

What I usually do for that class is use a max ported Trashcan with no jet. Take the jet holder fitting out and just run a straight number 4 line from solenoid to plate. This lets if flow all it will flow with no restriction.

Larger line and bottle valve won't hurt, but it likely won't help either. A .250 orifice solenoid also gets you a bit more flow, but you can't progress it.

And YES, a Crossbar with a number 4 line will pass more.

Don't know anything much about your motor, but I would bet the cam is holding you back some as well depending on who ground it for you. 132 is definitely light on MPH. I have 18* smallblocks that run that mph on a single bar plate, so something is off somewhere. If you still had the -1s..........well that's about the same head as a good 18* small block, but those MCs done right should move a lot of air

There is not 10 mph in your tune up.........I guarantee you that and you know your 60ft is way soft