Uhh, pretty sure the Super Scout was four sweep tubes driving eight. Meant for 11 meters.
Placing eight tubes in parallel presents a challenge to the design of the output circuit. There is a functional or "parasitic" capacitor to ground inside each tube from the plate cap to ground. The tube's internal structure is the root of this. With the tubes' plate caps wired in parallel, the capacitance of the eight tubes adds up. To make the output coil resonate at 27 MHz, it has to be cut down so small that it can be hard to get a proper impedance match and couple the output power to the antenna efficiently.
If the Load control goes all the way to full mesh without showing a peak, I would put a 100 pf capacitor in parallel with it. It will have to be a stout specimen with plenty of metal in it. A ceramic capacitor won't have enough metal for the job unless it has a really high voltage rating.
One other way to improve the current rating of a capacitor is to use two, three or more in parallel. Silver-mica capacitors tend to handle high RF current better than ceramic disc types, but only if they are big enough.
Old military-surplus "transmitting mica" capacitors with a threaded brass insert at each end are meant for high current if you can find one.
100 pf might or might not be enough to do the job, but it will at least help. And if it moves the peak setting of the Load control back between the end stops, that's what matters.
I would be worrying more about the plate tune. If it doesn't have the "Twin Peaks" this can be hard on the tubes.
73
