cutting the rear frame under the seat

on my 77 kz650 i have added solid struts and lowered the rear 3 inches ...i am thinkingof taking the stock fender and rear plastic cowl of the bike ...i have two different fenders i was thinking of using ....but under the seat there is where the plastic cowl attaches to the frame ...if i cut this off do i need to do anything to be sure the frame isnt at risk ...i have seen a few bikes with the piece off it ..but i was just curious about it ...any help would be welcome thanks

any plastic on the back end is for cosmetics. it is not structural. so it will not weaken the frame to remove it.

Cut away.