Ok some updates to this... I've been learning about my mower and playing

Removed chains, inspected and cleaned. All good.
Made a decision to get the reel and bedknife sharpened, since I'll get the clutch sorted at some point anyway, might as well make the disassembly worth while

Taken reel sprocket off, removed right side bearing cover screws, gone to do the left side and they're tight as. I've done some searching around on here information wise, and most things lead to taking the mower to professional or try use heat - or hole punch hitting into it counterclockwise. I seriously don't want to kill these screws so if there's anything I've missed?
Thanks
Stew