Lets Try This for Size

Unknown

I received my 29 Sedan Model R with an Essex sized trunk (small) plus it was quite ratted out on the bottom. Purchased another trunk (Kalee) that is 22" deep. THe trunk kind of overhangs the rear bumper by about 3-4" give or take. From some of the pics I've collected the 29 seems to have adapted to several sized trunks. What is the process and parts required to move the bumper out 3-4". It appears that the 2 inner braces need only be stretched but I'm not trying it till I ask and make sure I am overlooking some detail.

THanks

Jack