Ive modeled the Radio Shack VU series with the vhf-low elements removed and boom chopped, and it works fine for vhf-hi. No difference in vhf-hi gain, so if you have a RS VU series and no more vhf-low channels, chop away.I removed 4 longer ones at the back of the antenna, on an old VHF-UHF-FM Radio Shack antenna bought 10 years ago....( for the cottage )
However, I would be very leary of chopping the Winegard HD7084P because it has those short elements under the long elements, which may be for vhf-hi gain.