1100 shurshot fore end

[lifehog]

I just recieved this shurshot synthetic kit today for Christmas and the stock went on with no problems but the fore end wont go on all the way. Did anyone else have this problem? It seems to need a little trimming of the tabs on the inside but i didnt want to mess with it without some advice first.it says on the package it fits 1100/1187's. Thanks alot for the help.