Triumph Repair: 80 Spit bumper, rubber bumpers, frame mods

Question
Hi, I'd like to replace the black rubber bumpers on my 80 Spitfire with the chrome versions from say 77 on. I know it can be done, but the front under riders must be ground off to fit the smaller covers. I'd like to fit the front chrome bumper and NOT alter the frame (under riders). Any ideas? I was thinking if I cut the black front bumper to act as a cover for the grill and Under riders I could then fit the chrome bumper with no frame mods.
Thanks for your help.
Ken

Answer
Ken,

I have to admit that this question may be a bit beyond me.  I'm used to the Mk IV through late chrome bumper Spitfires.. I'm not sure what changes were made to the bonnet hinge area when the rubber bumpers were added.

Have you looked to see if the late chrome bumper over-riders will fit?  Say from a '78 vintage?

Cheers,

Jim